diff mbox series

[v4,64/80] drm/omap: dsi: cleanup channel usages

Message ID 20201124124538.660710-65-tomi.valkeinen@ti.com (mailing list archive)
State New
Headers show
Series Convert DSI code to use drm_mipi_dsi and drm_panel | expand

Commit Message

Tomi Valkeinen Nov. 24, 2020, 12:45 p.m. UTC
The "channel" usage in omap dsi driver is super confusing. We have three
different "channels":

1) DSI virtual channel ID. This is a number from 0 to 3, included in the
packet payload.

2) VC. This is a register block in the DSI IP. There are four of those
blocks. A VC is a DSI "pipeline", with defined fifo settings, data
source (cpu or dispc), and some other settings. It has no relation to
the 1).

3) dispc channel. It's the "pipeline" number dispc uses to send pixel
data.

To clean this up use the following names for each of the above: 1)
"channel" 2) "vc" 3) "dispc_channel"

This patch is mostly about renaming things, but as in some places 1) and
2) have gotten mixed up, additional changes were needed to untangle
them. This is mostly just adding a new parameter to some functions so
that we pass both the vc and the channel.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
---
 drivers/gpu/drm/omapdrm/dss/dsi.c | 315 +++++++++++++++---------------
 1 file changed, 158 insertions(+), 157 deletions(-)

Comments

Laurent Pinchart Dec. 1, 2020, 12:17 a.m. UTC | #1
Hi Tomi,

Thank you for the patch.

On Tue, Nov 24, 2020 at 02:45:22PM +0200, Tomi Valkeinen wrote:
> The "channel" usage in omap dsi driver is super confusing. We have three
> different "channels":
> 
> 1) DSI virtual channel ID. This is a number from 0 to 3, included in the
> packet payload.
> 
> 2) VC. This is a register block in the DSI IP. There are four of those
> blocks. A VC is a DSI "pipeline", with defined fifo settings, data
> source (cpu or dispc), and some other settings. It has no relation to
> the 1).

Lovely that it's called VC :-)

> 3) dispc channel. It's the "pipeline" number dispc uses to send pixel
> data.
> 
> To clean this up use the following names for each of the above: 1)
> "channel" 2) "vc" 3) "dispc_channel"

1) and 2) will still be prone to confusion :-S Would it help to name 2)
hw_vc or something similar ?

> This patch is mostly about renaming things, but as in some places 1) and
> 2) have gotten mixed up, additional changes were needed to untangle
> them. This is mostly just adding a new parameter to some functions so
> that we pass both the vc and the channel.

It would ease review if this could be split in two patches.

> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> ---
>  drivers/gpu/drm/omapdrm/dss/dsi.c | 315 +++++++++++++++---------------
>  1 file changed, 158 insertions(+), 157 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c
> index fbf05097612f..4ac82166edc3 100644
> --- a/drivers/gpu/drm/omapdrm/dss/dsi.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
> @@ -214,9 +214,9 @@ static void dsi_set_ulps_auto(struct dsi_data *dsi, bool enable);
>  static int dsi_display_init_dispc(struct dsi_data *dsi);
>  static void dsi_display_uninit_dispc(struct dsi_data *dsi);
>  
> -static int dsi_vc_send_null(struct dsi_data *dsi, int channel);
> +static int dsi_vc_send_null(struct dsi_data *dsi, int vc, int channel);
>  
> -static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
> +static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc,
>  				       const struct mipi_dsi_msg *msg);
>  
>  static void dsi_display_disable(struct omap_dss_device *dssdev);
> @@ -376,7 +376,7 @@ struct dsi_data {
>  	/* space for a copy used by the interrupt handler */
>  	struct dsi_isr_tables isr_tables_copy;
>  
> -	int update_channel;
> +	int update_vc;
>  #ifdef DSI_PERF_MEASURE
>  	unsigned int update_bytes;
>  #endif
> @@ -639,7 +639,7 @@ static void print_irq_status(u32 status)
>  #undef PIS
>  }
>  
> -static void print_irq_status_vc(int channel, u32 status)
> +static void print_irq_status_vc(int vc, u32 status)
>  {
>  	if (status == 0)
>  		return;
> @@ -650,7 +650,7 @@ static void print_irq_status_vc(int channel, u32 status)
>  #define PIS(x) (status & DSI_VC_IRQ_##x) ? (#x " ") : ""
>  
>  	pr_debug("DSI VC(%d) IRQ 0x%x: %s%s%s%s%s%s%s%s%s\n",
> -		channel,
> +		vc,
>  		status,
>  		PIS(CS),
>  		PIS(ECC_CORR),
> @@ -1031,7 +1031,7 @@ static int dsi_unregister_isr(struct dsi_data *dsi, omap_dsi_isr_t isr,
>  	return r;
>  }
>  
> -static int dsi_register_isr_vc(struct dsi_data *dsi, int channel,
> +static int dsi_register_isr_vc(struct dsi_data *dsi, int vc,
>  			       omap_dsi_isr_t isr, void *arg, u32 mask)
>  {
>  	unsigned long flags;
> @@ -1040,18 +1040,18 @@ static int dsi_register_isr_vc(struct dsi_data *dsi, int channel,
>  	spin_lock_irqsave(&dsi->irq_lock, flags);
>  
>  	r = _dsi_register_isr(isr, arg, mask,
> -			dsi->isr_tables.isr_table_vc[channel],
> -			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[channel]));
> +			dsi->isr_tables.isr_table_vc[vc],
> +			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[vc]));
>  
>  	if (r == 0)
> -		_omap_dsi_set_irqs_vc(dsi, channel);
> +		_omap_dsi_set_irqs_vc(dsi, vc);
>  
>  	spin_unlock_irqrestore(&dsi->irq_lock, flags);
>  
>  	return r;
>  }
>  
> -static int dsi_unregister_isr_vc(struct dsi_data *dsi, int channel,
> +static int dsi_unregister_isr_vc(struct dsi_data *dsi, int vc,
>  				 omap_dsi_isr_t isr, void *arg, u32 mask)
>  {
>  	unsigned long flags;
> @@ -1060,11 +1060,11 @@ static int dsi_unregister_isr_vc(struct dsi_data *dsi, int channel,
>  	spin_lock_irqsave(&dsi->irq_lock, flags);
>  
>  	r = _dsi_unregister_isr(isr, arg, mask,
> -			dsi->isr_tables.isr_table_vc[channel],
> -			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[channel]));
> +			dsi->isr_tables.isr_table_vc[vc],
> +			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[vc]));
>  
>  	if (r == 0)
> -		_omap_dsi_set_irqs_vc(dsi, channel);
> +		_omap_dsi_set_irqs_vc(dsi, vc);
>  
>  	spin_unlock_irqrestore(&dsi->irq_lock, flags);
>  
> @@ -2232,9 +2232,9 @@ static int dsi_force_tx_stop_mode_io(struct dsi_data *dsi)
>  	return 0;
>  }
>  
> -static bool dsi_vc_is_enabled(struct dsi_data *dsi, int channel)
> +static bool dsi_vc_is_enabled(struct dsi_data *dsi, int vc)
>  {
> -	return REG_GET(dsi, DSI_VC_CTRL(channel), 0, 0);
> +	return REG_GET(dsi, DSI_VC_CTRL(vc), 0, 0);
>  }
>  
>  static void dsi_packet_sent_handler_vp(void *data, u32 mask)
> @@ -2242,14 +2242,14 @@ static void dsi_packet_sent_handler_vp(void *data, u32 mask)
>  	struct dsi_packet_sent_handler_data *vp_data =
>  		(struct dsi_packet_sent_handler_data *) data;
>  	struct dsi_data *dsi = vp_data->dsi;
> -	const int channel = dsi->update_channel;
> +	const int vc = dsi->update_vc;
>  	u8 bit = dsi->te_enabled ? 30 : 31;
>  
> -	if (REG_GET(dsi, DSI_VC_TE(channel), bit, bit) == 0)
> +	if (REG_GET(dsi, DSI_VC_TE(vc), bit, bit) == 0)
>  		complete(vp_data->completion);
>  }
>  
> -static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
> +static int dsi_sync_vc_vp(struct dsi_data *dsi, int vc)
>  {
>  	DECLARE_COMPLETION_ONSTACK(completion);
>  	struct dsi_packet_sent_handler_data vp_data = {
> @@ -2261,13 +2261,13 @@ static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
>  
>  	bit = dsi->te_enabled ? 30 : 31;
>  
> -	r = dsi_register_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
> +	r = dsi_register_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
>  		&vp_data, DSI_VC_IRQ_PACKET_SENT);
>  	if (r)
>  		goto err0;
>  
>  	/* Wait for completion only if TE_EN/TE_START is still set */
> -	if (REG_GET(dsi, DSI_VC_TE(channel), bit, bit)) {
> +	if (REG_GET(dsi, DSI_VC_TE(vc), bit, bit)) {
>  		if (wait_for_completion_timeout(&completion,
>  				msecs_to_jiffies(10)) == 0) {
>  			DSSERR("Failed to complete previous frame transfer\n");
> @@ -2276,12 +2276,12 @@ static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
>  		}
>  	}
>  
> -	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
> +	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
>  		&vp_data, DSI_VC_IRQ_PACKET_SENT);
>  
>  	return 0;
>  err1:
> -	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
> +	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
>  		&vp_data, DSI_VC_IRQ_PACKET_SENT);
>  err0:
>  	return r;
> @@ -2292,13 +2292,13 @@ static void dsi_packet_sent_handler_l4(void *data, u32 mask)
>  	struct dsi_packet_sent_handler_data *l4_data =
>  		(struct dsi_packet_sent_handler_data *) data;
>  	struct dsi_data *dsi = l4_data->dsi;
> -	const int channel = dsi->update_channel;
> +	const int vc = dsi->update_vc;
>  
> -	if (REG_GET(dsi, DSI_VC_CTRL(channel), 5, 5) == 0)
> +	if (REG_GET(dsi, DSI_VC_CTRL(vc), 5, 5) == 0)
>  		complete(l4_data->completion);
>  }
>  
> -static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
> +static int dsi_sync_vc_l4(struct dsi_data *dsi, int vc)
>  {
>  	DECLARE_COMPLETION_ONSTACK(completion);
>  	struct dsi_packet_sent_handler_data l4_data = {
> @@ -2307,13 +2307,13 @@ static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
>  	};
>  	int r = 0;
>  
> -	r = dsi_register_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
> +	r = dsi_register_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
>  		&l4_data, DSI_VC_IRQ_PACKET_SENT);
>  	if (r)
>  		goto err0;
>  
>  	/* Wait for completion only if TX_FIFO_NOT_EMPTY is still set */
> -	if (REG_GET(dsi, DSI_VC_CTRL(channel), 5, 5)) {
> +	if (REG_GET(dsi, DSI_VC_CTRL(vc), 5, 5)) {
>  		if (wait_for_completion_timeout(&completion,
>  				msecs_to_jiffies(10)) == 0) {
>  			DSSERR("Failed to complete previous l4 transfer\n");
> @@ -2322,47 +2322,47 @@ static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
>  		}
>  	}
>  
> -	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
> +	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
>  		&l4_data, DSI_VC_IRQ_PACKET_SENT);
>  
>  	return 0;
>  err1:
> -	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
> +	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
>  		&l4_data, DSI_VC_IRQ_PACKET_SENT);
>  err0:
>  	return r;
>  }
>  
> -static int dsi_sync_vc(struct dsi_data *dsi, int channel)
> +static int dsi_sync_vc(struct dsi_data *dsi, int vc)
>  {
>  	WARN_ON(!dsi_bus_is_locked(dsi));
>  
>  	WARN_ON(in_interrupt());
>  
> -	if (!dsi_vc_is_enabled(dsi, channel))
> +	if (!dsi_vc_is_enabled(dsi, vc))
>  		return 0;
>  
> -	switch (dsi->vc[channel].source) {
> +	switch (dsi->vc[vc].source) {
>  	case DSI_VC_SOURCE_VP:
> -		return dsi_sync_vc_vp(dsi, channel);
> +		return dsi_sync_vc_vp(dsi, vc);
>  	case DSI_VC_SOURCE_L4:
> -		return dsi_sync_vc_l4(dsi, channel);
> +		return dsi_sync_vc_l4(dsi, vc);
>  	default:
>  		BUG();
>  		return -EINVAL;
>  	}
>  }
>  
> -static int dsi_vc_enable(struct dsi_data *dsi, int channel, bool enable)
> +static int dsi_vc_enable(struct dsi_data *dsi, int vc, bool enable)
>  {
> -	DSSDBG("dsi_vc_enable channel %d, enable %d\n",
> -			channel, enable);
> +	DSSDBG("dsi_vc_enable vc %d, enable %d\n",
> +			vc, enable);
>  
>  	enable = enable ? 1 : 0;
>  
> -	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 0, 0);
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 0, 0);
>  
> -	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(channel), 0, enable)) {
> +	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(vc), 0, enable)) {
>  		DSSERR("Failed to set dsi_vc_enable to %d\n", enable);
>  		return -EIO;
>  	}
> @@ -2370,17 +2370,17 @@ static int dsi_vc_enable(struct dsi_data *dsi, int channel, bool enable)
>  	return 0;
>  }
>  
> -static void dsi_vc_initial_config(struct dsi_data *dsi, int channel)
> +static void dsi_vc_initial_config(struct dsi_data *dsi, int vc)
>  {
>  	u32 r;
>  
> -	DSSDBG("Initial config of virtual channel %d", channel);
> +	DSSDBG("Initial config of VC %d", vc);
>  
> -	r = dsi_read_reg(dsi, DSI_VC_CTRL(channel));
> +	r = dsi_read_reg(dsi, DSI_VC_CTRL(vc));
>  
>  	if (FLD_GET(r, 15, 15)) /* VC_BUSY */
>  		DSSERR("VC(%d) busy when trying to configure it!\n",
> -				channel);
> +				vc);
>  
>  	r = FLD_MOD(r, 0, 1, 1); /* SOURCE, 0 = L4 */
>  	r = FLD_MOD(r, 0, 2, 2); /* BTA_SHORT_EN  */
> @@ -2395,76 +2395,76 @@ static void dsi_vc_initial_config(struct dsi_data *dsi, int channel)
>  	r = FLD_MOD(r, 4, 29, 27); /* DMA_RX_REQ_NB = no dma */
>  	r = FLD_MOD(r, 4, 23, 21); /* DMA_TX_REQ_NB = no dma */
>  
> -	dsi_write_reg(dsi, DSI_VC_CTRL(channel), r);
> +	dsi_write_reg(dsi, DSI_VC_CTRL(vc), r);
>  
> -	dsi->vc[channel].source = DSI_VC_SOURCE_L4;
> +	dsi->vc[vc].source = DSI_VC_SOURCE_L4;
>  }
>  
> -static int dsi_vc_config_source(struct dsi_data *dsi, int channel,
> +static int dsi_vc_config_source(struct dsi_data *dsi, int vc,
>  				enum dsi_vc_source source)
>  {
> -	if (dsi->vc[channel].source == source)
> +	if (dsi->vc[vc].source == source)
>  		return 0;
>  
> -	DSSDBG("Source config of virtual channel %d", channel);
> +	DSSDBG("Source config of VC %d", vc);
>  
> -	dsi_sync_vc(dsi, channel);
> +	dsi_sync_vc(dsi, vc);
>  
> -	dsi_vc_enable(dsi, channel, 0);
> +	dsi_vc_enable(dsi, vc, 0);
>  
>  	/* VC_BUSY */
> -	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(channel), 15, 0)) {
> -		DSSERR("vc(%d) busy when trying to config for VP\n", channel);
> +	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(vc), 15, 0)) {
> +		DSSERR("vc(%d) busy when trying to config for VP\n", vc);
>  		return -EIO;
>  	}
>  
>  	/* SOURCE, 0 = L4, 1 = video port */
> -	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), source, 1, 1);
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), source, 1, 1);
>  
>  	/* DCS_CMD_ENABLE */
>  	if (dsi->data->quirks & DSI_QUIRK_DCS_CMD_CONFIG_VC) {
>  		bool enable = source == DSI_VC_SOURCE_VP;
> -		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 30, 30);
> +		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 30, 30);
>  	}
>  
> -	dsi_vc_enable(dsi, channel, 1);
> +	dsi_vc_enable(dsi, vc, 1);
>  
> -	dsi->vc[channel].source = source;
> +	dsi->vc[vc].source = source;
>  
>  	return 0;
>  }
>  
> -static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int channel,
> +static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
>  		bool enable)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  
> -	DSSDBG("dsi_vc_enable_hs(%d, %d)\n", channel, enable);
> +	DSSDBG("dsi_vc_enable_hs(%d, %d)\n", vc, enable);
>  
>  	WARN_ON(!dsi_bus_is_locked(dsi));
>  
> -	dsi_vc_enable(dsi, channel, 0);
> +	dsi_vc_enable(dsi, vc, 0);
>  	dsi_if_enable(dsi, 0);
>  
> -	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 9, 9);
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 9, 9);
>  
> -	dsi_vc_enable(dsi, channel, 1);
> +	dsi_vc_enable(dsi, vc, 1);
>  	dsi_if_enable(dsi, 1);
>  
>  	dsi_force_tx_stop_mode_io(dsi);
>  
>  	/* start the DDR clock by sending a NULL packet */
>  	if (dsi->vm_timings.ddr_clk_always_on && enable)
> -		dsi_vc_send_null(dsi, channel);
> +		dsi_vc_send_null(dsi, vc, dsi->dsidev->channel);
>  
>  	dsi->in_lp_mode = !enable;
>  }
>  
> -static void dsi_vc_flush_long_data(struct dsi_data *dsi, int channel)
> +static void dsi_vc_flush_long_data(struct dsi_data *dsi, int vc)
>  {
> -	while (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
> +	while (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
>  		u32 val;
> -		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
> +		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
>  		DSSDBG("\t\tb1 %#02x b2 %#02x b3 %#02x b4 %#02x\n",
>  				(val >> 0) & 0xff,
>  				(val >> 8) & 0xff,
> @@ -2510,13 +2510,13 @@ static void dsi_show_rx_ack_with_err(u16 err)
>  		DSSERR("\t\tDSI Protocol Violation\n");
>  }
>  
> -static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
> +static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int vc)
>  {
>  	/* RX_FIFO_NOT_EMPTY */
> -	while (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
> +	while (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
>  		u32 val;
>  		u8 dt;
> -		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
> +		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
>  		DSSERR("\trawval %#08x\n", val);
>  		dt = FLD_GET(val, 5, 0);
>  		if (dt == MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT) {
> @@ -2531,7 +2531,7 @@ static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
>  		} else if (dt == MIPI_DSI_RX_DCS_LONG_READ_RESPONSE) {
>  			DSSERR("\tDCS long response, len %d\n",
>  					FLD_GET(val, 23, 8));
> -			dsi_vc_flush_long_data(dsi, channel);
> +			dsi_vc_flush_long_data(dsi, vc);
>  		} else {
>  			DSSERR("\tunknown datatype 0x%02x\n", dt);
>  		}
> @@ -2539,35 +2539,35 @@ static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
>  	return 0;
>  }
>  
> -static int dsi_vc_send_bta(struct dsi_data *dsi, int channel)
> +static int dsi_vc_send_bta(struct dsi_data *dsi, int vc)
>  {
>  	if (dsi->debug_write || dsi->debug_read)
> -		DSSDBG("dsi_vc_send_bta %d\n", channel);
> +		DSSDBG("dsi_vc_send_bta %d\n", vc);
>  
>  	WARN_ON(!dsi_bus_is_locked(dsi));
>  
>  	/* RX_FIFO_NOT_EMPTY */
> -	if (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
> +	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
>  		DSSERR("rx fifo not empty when sending BTA, dumping data:\n");
> -		dsi_vc_flush_receive_data(dsi, channel);
> +		dsi_vc_flush_receive_data(dsi, vc);
>  	}
>  
> -	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 1, 6, 6); /* BTA_EN */
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 1, 6, 6); /* BTA_EN */
>  
>  	/* flush posted write */
> -	dsi_read_reg(dsi, DSI_VC_CTRL(channel));
> +	dsi_read_reg(dsi, DSI_VC_CTRL(vc));
>  
>  	return 0;
>  }
>  
> -static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
> +static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int vc)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	DECLARE_COMPLETION_ONSTACK(completion);
>  	int r = 0;
>  	u32 err;
>  
> -	r = dsi_register_isr_vc(dsi, channel, dsi_completion_handler,
> +	r = dsi_register_isr_vc(dsi, vc, dsi_completion_handler,
>  			&completion, DSI_VC_IRQ_BTA);
>  	if (r)
>  		goto err0;
> @@ -2577,7 +2577,7 @@ static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
>  	if (r)
>  		goto err1;
>  
> -	r = dsi_vc_send_bta(dsi, channel);
> +	r = dsi_vc_send_bta(dsi, vc);
>  	if (r)
>  		goto err2;
>  
> @@ -2598,14 +2598,15 @@ static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
>  	dsi_unregister_isr(dsi, dsi_completion_handler, &completion,
>  			DSI_IRQ_ERROR_MASK);
>  err1:
> -	dsi_unregister_isr_vc(dsi, channel, dsi_completion_handler,
> +	dsi_unregister_isr_vc(dsi, vc, dsi_completion_handler,
>  			&completion, DSI_VC_IRQ_BTA);
>  err0:
>  	return r;
>  }
>  
> -static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int channel,
> -					    u8 data_type, u16 len, u8 ecc)
> +static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int vc,
> +					    int channel, u8 data_type, u16 len,
> +					    u8 ecc)
>  {
>  	u32 val;
>  	u8 data_id;
> @@ -2615,12 +2616,12 @@ static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int channel,
>  	data_id = data_type | channel << 6;
>  
>  	val = FLD_VAL(data_id, 7, 0) | FLD_VAL(len, 23, 8) |
> -		FLD_VAL(ecc, 31, 24);
> +	      FLD_VAL(ecc, 31, 24);
>  
> -	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_HEADER(channel), val);
> +	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_HEADER(vc), val);
>  }
>  
> -static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int channel,
> +static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int vc,
>  					     u8 b1, u8 b2, u8 b3, u8 b4)
>  {
>  	u32 val;
> @@ -2630,10 +2631,10 @@ static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int channel,
>  /*	DSSDBG("\twriting %02x, %02x, %02x, %02x (%#010x)\n",
>  			b1, b2, b3, b4, val); */
>  
> -	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_PAYLOAD(channel), val);
> +	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_PAYLOAD(vc), val);
>  }
>  
> -static int dsi_vc_send_long(struct dsi_data *dsi,
> +static int dsi_vc_send_long(struct dsi_data *dsi, int vc,
>  			    const struct mipi_dsi_msg *msg)
>  {
>  	/*u32 val; */
> @@ -2646,14 +2647,14 @@ static int dsi_vc_send_long(struct dsi_data *dsi,
>  		DSSDBG("dsi_vc_send_long, %d bytes\n", msg->tx_len);
>  
>  	/* len + header */
> -	if (dsi->vc[msg->channel].tx_fifo_size * 32 * 4 < msg->tx_len + 4) {
> +	if (dsi->vc[vc].tx_fifo_size * 32 * 4 < msg->tx_len + 4) {
>  		DSSERR("unable to send long packet: packet too long.\n");
>  		return -EINVAL;
>  	}
>  
> -	dsi_vc_config_source(dsi, msg->channel, DSI_VC_SOURCE_L4);
> +	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
>  
> -	dsi_vc_write_long_header(dsi, msg->channel, msg->type, msg->tx_len, 0);
> +	dsi_vc_write_long_header(dsi, vc, msg->channel, msg->type, msg->tx_len, 0);
>  
>  	p = msg->tx_buf;
>  	for (i = 0; i < msg->tx_len >> 2; i++) {
> @@ -2665,7 +2666,7 @@ static int dsi_vc_send_long(struct dsi_data *dsi,
>  		b3 = *p++;
>  		b4 = *p++;
>  
> -		dsi_vc_write_long_payload(dsi, msg->channel, b1, b2, b3, b4);
> +		dsi_vc_write_long_payload(dsi, vc, b1, b2, b3, b4);
>  	}
>  
>  	i = msg->tx_len % 4;
> @@ -2690,13 +2691,13 @@ static int dsi_vc_send_long(struct dsi_data *dsi,
>  			break;
>  		}
>  
> -		dsi_vc_write_long_payload(dsi, msg->channel, b1, b2, b3, 0);
> +		dsi_vc_write_long_payload(dsi, vc, b1, b2, b3, 0);
>  	}
>  
>  	return r;
>  }
>  
> -static int dsi_vc_send_short(struct dsi_data *dsi,
> +static int dsi_vc_send_short(struct dsi_data *dsi, int vc,
>  			     const struct mipi_dsi_msg *msg)
>  {
>  	struct mipi_dsi_packet pkt;
> @@ -2710,11 +2711,11 @@ static int dsi_vc_send_short(struct dsi_data *dsi,
>  
>  	if (dsi->debug_write)
>  		DSSDBG("dsi_vc_send_short(ch%d, dt %#x, b1 %#x, b2 %#x)\n",
> -		       msg->channel, msg->type, pkt.header[1], pkt.header[2]);
> +		       vc, msg->type, pkt.header[1], pkt.header[2]);
>  
> -	dsi_vc_config_source(dsi, msg->channel, DSI_VC_SOURCE_L4);
> +	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
>  
> -	if (FLD_GET(dsi_read_reg(dsi, DSI_VC_CTRL(msg->channel)), 16, 16)) {
> +	if (FLD_GET(dsi_read_reg(dsi, DSI_VC_CTRL(vc)), 16, 16)) {
>  		DSSERR("ERROR FIFO FULL, aborting transfer\n");
>  		return -EINVAL;
>  	}
> @@ -2722,31 +2723,31 @@ static int dsi_vc_send_short(struct dsi_data *dsi,
>  	r = pkt.header[3] << 24 | pkt.header[2] << 16 | pkt.header[1] << 8 |
>  	    pkt.header[0];
>  
> -	dsi_write_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(msg->channel), r);
> +	dsi_write_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc), r);
>  
>  	return 0;
>  }
>  
> -static int dsi_vc_send_null(struct dsi_data *dsi, int channel)
> +static int dsi_vc_send_null(struct dsi_data *dsi, int vc, int channel)
>  {
>  	const struct mipi_dsi_msg msg = {
>  		.channel = channel,
>  		.type = MIPI_DSI_NULL_PACKET,
>  	};
>  
> -	return dsi_vc_send_long(dsi, &msg);
> +	return dsi_vc_send_long(dsi, vc, &msg);
>  }
>  
> -static int dsi_vc_write_common(struct omap_dss_device *dssdev,
> +static int dsi_vc_write_common(struct omap_dss_device *dssdev, int vc,
>  			       const struct mipi_dsi_msg *msg)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	int r;
>  
>  	if (mipi_dsi_packet_format_is_short(msg->type))
> -		r = dsi_vc_send_short(dsi, msg);
> +		r = dsi_vc_send_short(dsi, vc, msg);
>  	else
> -		r = dsi_vc_send_long(dsi, msg);
> +		r = dsi_vc_send_long(dsi, vc, msg);
>  
>  	if (r < 0)
>  		return r;
> @@ -2758,23 +2759,23 @@ static int dsi_vc_write_common(struct omap_dss_device *dssdev,
>  	 * In that case we can return early.
>  	 */
>  
> -	r = dsi_vc_send_bta_sync(dssdev, msg->channel);
> +	r = dsi_vc_send_bta_sync(dssdev, vc);
>  	if (r) {
>  		DSSERR("bta sync failed\n");
>  		return r;
>  	}
>  
>  	/* RX_FIFO_NOT_EMPTY */
> -	if (REG_GET(dsi, DSI_VC_CTRL(msg->channel), 20, 20)) {
> +	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
>  		DSSERR("rx fifo not empty after write, dumping data:\n");
> -		dsi_vc_flush_receive_data(dsi, msg->channel);
> +		dsi_vc_flush_receive_data(dsi, vc);
>  		return -EIO;
>  	}
>  
>  	return 0;
>  }
>  
> -static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
> +static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int vc, u8 *buf,
>  			       int buflen, enum dss_dsi_content_type type)
>  {
>  	u32 val;
> @@ -2782,13 +2783,13 @@ static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
>  	int r;
>  
>  	/* RX_FIFO_NOT_EMPTY */
> -	if (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20) == 0) {
> +	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20) == 0) {
>  		DSSERR("RX fifo empty when trying to read.\n");
>  		r = -EIO;
>  		goto err;
>  	}
>  
> -	val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
> +	val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
>  	if (dsi->debug_read)
>  		DSSDBG("\theader: %08x\n", val);
>  	dt = FLD_GET(val, 5, 0);
> @@ -2852,7 +2853,7 @@ static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
>  		for (w = 0; w < len + 2;) {
>  			int b;
>  			val = dsi_read_reg(dsi,
> -				DSI_VC_SHORT_PACKET_HEADER(channel));
> +				DSI_VC_SHORT_PACKET_HEADER(vc));
>  			if (dsi->debug_read)
>  				DSSDBG("\t\t%02x %02x %02x %02x\n",
>  						(val >> 0) & 0xff,
> @@ -2876,32 +2877,31 @@ static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
>  	}
>  
>  err:
> -	DSSERR("dsi_vc_read_rx_fifo(ch %d type %s) failed\n", channel,
> +	DSSERR("dsi_vc_read_rx_fifo(vc %d type %s) failed\n", vc,
>  		type == DSS_DSI_CONTENT_GENERIC ? "GENERIC" : "DCS");
>  
>  	return r;
>  }
>  
> -static int dsi_vc_dcs_read(struct omap_dss_device *dssdev,
> +static int dsi_vc_dcs_read(struct omap_dss_device *dssdev, int vc,
>  			   const struct mipi_dsi_msg *msg)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	u8 cmd = ((u8 *)msg->tx_buf)[0];
> -	u8 channel = msg->channel;
>  	int r;
>  
>  	if (dsi->debug_read)
> -		DSSDBG("%s(ch %d, cmd %x)\n", __func__, channel, cmd);
> +		DSSDBG("%s(ch %d, cmd %x)\n", __func__, vc, cmd);
>  
> -	r = dsi_vc_send_short(dsi, msg);
> +	r = dsi_vc_send_short(dsi, vc, msg);
>  	if (r)
>  		goto err;
>  
> -	r = dsi_vc_send_bta_sync(dssdev, channel);
> +	r = dsi_vc_send_bta_sync(dssdev, vc);
>  	if (r)
>  		goto err;
>  
> -	r = dsi_vc_read_rx_fifo(dsi, channel, msg->rx_buf, msg->rx_len,
> +	r = dsi_vc_read_rx_fifo(dsi, vc, msg->rx_buf, msg->rx_len,
>  		DSS_DSI_CONTENT_DCS);
>  	if (r < 0)
>  		goto err;
> @@ -2913,25 +2913,25 @@ static int dsi_vc_dcs_read(struct omap_dss_device *dssdev,
>  
>  	return 0;
>  err:
> -	DSSERR("%s(ch %d, cmd 0x%02x) failed\n", __func__,  msg->channel, cmd);
> +	DSSERR("%s(ch %d, cmd 0x%02x) failed\n", __func__,  vc, cmd);
>  	return r;
>  }
>  
> -static int dsi_vc_generic_read(struct omap_dss_device *dssdev,
> +static int dsi_vc_generic_read(struct omap_dss_device *dssdev, int vc,
>  			       const struct mipi_dsi_msg *msg)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	int r;
>  
> -	r = dsi_vc_send_short(dsi, msg);
> +	r = dsi_vc_send_short(dsi, vc, msg);
>  	if (r)
>  		goto err;
>  
> -	r = dsi_vc_send_bta_sync(dssdev, msg->channel);
> +	r = dsi_vc_send_bta_sync(dssdev, vc);
>  	if (r)
>  		goto err;
>  
> -	r = dsi_vc_read_rx_fifo(dsi, msg->channel, msg->rx_buf, msg->rx_len,
> +	r = dsi_vc_read_rx_fifo(dsi, vc, msg->rx_buf, msg->rx_len,
>  		DSS_DSI_CONTENT_GENERIC);
>  	if (r < 0)
>  		goto err;
> @@ -2943,7 +2943,7 @@ static int dsi_vc_generic_read(struct omap_dss_device *dssdev,
>  
>  	return 0;
>  err:
> -	DSSERR("%s(ch %d, reqlen %d) failed\n", __func__,  msg->channel, msg->tx_len);
> +	DSSERR("%s(ch %d, reqlen %d) failed\n", __func__,  vc, msg->tx_len);
>  	return r;
>  }
>  
> @@ -3631,7 +3631,7 @@ static int dsi_configure_pins(struct dsi_data *dsi,
>  	return 0;
>  }
>  
> -static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
> +static void dsi_enable_video_output(struct omap_dss_device *dssdev, int vc)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	int bpp = mipi_dsi_pixel_format_to_bpp(dsi->pix_fmt);
> @@ -3665,17 +3665,17 @@ static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
>  		}
>  
>  		dsi_if_enable(dsi, false);
> -		dsi_vc_enable(dsi, channel, false);
> +		dsi_vc_enable(dsi, vc, false);
>  
>  		/* MODE, 1 = video mode */
> -		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 1, 4, 4);
> +		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 1, 4, 4);
>  
>  		word_count = DIV_ROUND_UP(dsi->vm.hactive * bpp, 8);
>  
> -		dsi_vc_write_long_header(dsi, channel, data_type,
> +		dsi_vc_write_long_header(dsi, vc, dsi->dsidev->channel, data_type,
>  				word_count, 0);
>  
> -		dsi_vc_enable(dsi, channel, true);
> +		dsi_vc_enable(dsi, vc, true);
>  		dsi_if_enable(dsi, true);
>  	}
>  
> @@ -3688,7 +3688,7 @@ static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
>  err_mgr_enable:
>  	if (dsi->mode == OMAP_DSS_DSI_VIDEO_MODE) {
>  		dsi_if_enable(dsi, false);
> -		dsi_vc_enable(dsi, channel, false);
> +		dsi_vc_enable(dsi, vc, false);
>  	}
>  err_pix_fmt:
>  	dsi_display_uninit_dispc(dsi);
> @@ -3696,18 +3696,18 @@ static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
>  	return;
>  }
>  
> -static void dsi_disable_video_output(struct omap_dss_device *dssdev, int channel)
> +static void dsi_disable_video_output(struct omap_dss_device *dssdev, int vc)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  
>  	if (dsi->mode == OMAP_DSS_DSI_VIDEO_MODE) {
>  		dsi_if_enable(dsi, false);
> -		dsi_vc_enable(dsi, channel, false);
> +		dsi_vc_enable(dsi, vc, false);
>  
>  		/* MODE, 0 = command mode */
> -		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 0, 4, 4);
> +		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 0, 4, 4);
>  
> -		dsi_vc_enable(dsi, channel, true);
> +		dsi_vc_enable(dsi, vc, true);
>  		dsi_if_enable(dsi, true);
>  	}
>  
> @@ -3740,14 +3740,14 @@ static void dsi_update_screen_dispc(struct dsi_data *dsi)
>  	unsigned int packet_len;
>  	u32 l;
>  	int r;
> -	const unsigned channel = dsi->update_channel;
> +	const unsigned vc = dsi->update_vc;
>  	const unsigned int line_buf_size = dsi->line_buffer_size;
>  	u16 w = dsi->vm.hactive;
>  	u16 h = dsi->vm.vactive;
>  
>  	DSSDBG("dsi_update_screen_dispc(%dx%d)\n", w, h);
>  
> -	dsi_vc_config_source(dsi, channel, DSI_VC_SOURCE_VP);
> +	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_VP);
>  
>  	bytespp	= mipi_dsi_pixel_format_to_bpp(dsi->pix_fmt) / 8;
>  	bytespl = w * bytespp;
> @@ -3768,16 +3768,16 @@ static void dsi_update_screen_dispc(struct dsi_data *dsi)
>  		total_len += (bytespf % packet_payload) + 1;
>  
>  	l = FLD_VAL(total_len, 23, 0); /* TE_SIZE */
> -	dsi_write_reg(dsi, DSI_VC_TE(channel), l);
> +	dsi_write_reg(dsi, DSI_VC_TE(vc), l);
>  
> -	dsi_vc_write_long_header(dsi, channel, MIPI_DSI_DCS_LONG_WRITE,
> +	dsi_vc_write_long_header(dsi, vc, dsi->dsidev->channel, MIPI_DSI_DCS_LONG_WRITE,
>  		packet_len, 0);
>  
>  	if (dsi->te_enabled)
>  		l = FLD_MOD(l, 1, 30, 30); /* TE_EN */
>  	else
>  		l = FLD_MOD(l, 1, 31, 31); /* TE_START */
> -	dsi_write_reg(dsi, DSI_VC_TE(channel), l);
> +	dsi_write_reg(dsi, DSI_VC_TE(vc), l);
>  
>  	/* We put SIDLEMODE to no-idle for the duration of the transfer,
>  	 * because DSS interrupts are not capable of waking up the CPU and the
> @@ -3800,7 +3800,7 @@ static void dsi_update_screen_dispc(struct dsi_data *dsi)
>  		 * for TE is longer than the timer allows */
>  		REG_FLD_MOD(dsi, DSI_TIMING2, 0, 15, 15); /* LP_RX_TO */
>  
> -		dsi_vc_send_bta(dsi, channel);
> +		dsi_vc_send_bta(dsi, vc);
>  
>  #ifdef DSI_CATCH_MISSING_TE
>  		mod_timer(&dsi->te_timer, jiffies + msecs_to_jiffies(250));
> @@ -3882,7 +3882,7 @@ static int _dsi_update(struct dsi_data *dsi)
>  	return 0;
>  }
>  
> -static int _dsi_send_nop(struct dsi_data *dsi, int channel)
> +static int _dsi_send_nop(struct dsi_data *dsi, int vc, int channel)
>  {
>  	const u8 payload[] = { MIPI_DCS_NOP };
>  	const struct mipi_dsi_msg msg = {
> @@ -3894,10 +3894,10 @@ static int _dsi_send_nop(struct dsi_data *dsi, int channel)
>  
>  	WARN_ON(!dsi_bus_is_locked(dsi));
>  
> -	return _omap_dsi_host_transfer(dsi, &msg);
> +	return _omap_dsi_host_transfer(dsi, vc, &msg);
>  }
>  
> -static int dsi_update_channel(struct omap_dss_device *dssdev, int channel)
> +static int dsi_update_channel(struct omap_dss_device *dssdev, int vc)
>  {
>  	struct dsi_data *dsi = to_dsi_data(dssdev);
>  	int r;
> @@ -3914,17 +3914,17 @@ static int dsi_update_channel(struct omap_dss_device *dssdev, int channel)
>  		goto err;
>  	}
>  
> -	DSSDBG("dsi_update_channel: %d", channel);
> +	DSSDBG("dsi_update_channel: %d", vc);
>  
>  	dsi_set_ulps_auto(dsi, false);
>  
> -	r = _dsi_send_nop(dsi, channel);
> +	r = _dsi_send_nop(dsi, vc, dsi->dsidev->channel);
>  	if (r < 0) {
>  		DSSWARN("failed to send nop between frames: %d\n", r);
>  		goto err;
>  	}
>  
> -	dsi->update_channel = channel;
> +	dsi->update_vc = vc;
>  
>  	if (dsi->te_enabled && dsi->te_gpio) {
>  		schedule_delayed_work(&dsi->te_timeout_work,
> @@ -3973,10 +3973,10 @@ static int dsi_configure_dispc_clocks(struct dsi_data *dsi)
>  
>  static int dsi_display_init_dispc(struct dsi_data *dsi)
>  {
> -	enum omap_channel channel = dsi->output.dispc_channel;
> +	enum omap_channel dispc_channel = dsi->output.dispc_channel;
>  	int r;
>  
> -	dss_select_lcd_clk_source(dsi->dss, channel, dsi->module_id == 0 ?
> +	dss_select_lcd_clk_source(dsi->dss, dispc_channel, dsi->module_id == 0 ?
>  			DSS_CLK_SRC_PLL1_1 :
>  			DSS_CLK_SRC_PLL2_1);
>  
> @@ -4012,19 +4012,19 @@ static int dsi_display_init_dispc(struct dsi_data *dsi)
>  		dss_mgr_unregister_framedone_handler(&dsi->output,
>  				dsi_framedone_irq_callback, dsi);
>  err:
> -	dss_select_lcd_clk_source(dsi->dss, channel, DSS_CLK_SRC_FCK);
> +	dss_select_lcd_clk_source(dsi->dss, dispc_channel, DSS_CLK_SRC_FCK);
>  	return r;
>  }
>  
>  static void dsi_display_uninit_dispc(struct dsi_data *dsi)
>  {
> -	enum omap_channel channel = dsi->output.dispc_channel;
> +	enum omap_channel dispc_channel = dsi->output.dispc_channel;
>  
>  	if (dsi->mode == OMAP_DSS_DSI_CMD_MODE)
>  		dss_mgr_unregister_framedone_handler(&dsi->output,
>  				dsi_framedone_irq_callback, dsi);
>  
> -	dss_select_lcd_clk_source(dsi->dss, channel, DSS_CLK_SRC_FCK);
> +	dss_select_lcd_clk_source(dsi->dss, dispc_channel, DSS_CLK_SRC_FCK);
>  }
>  
>  static int dsi_configure_dsi_clocks(struct dsi_data *dsi)
> @@ -4841,12 +4841,12 @@ static int dsi_set_config(struct omap_dss_device *dssdev,
>  }
>  
>  /*
> - * Return a hardcoded channel for the DSI output. This should work for
> + * Return a hardcoded dispc channel for the DSI output. This should work for
>   * current use cases, but this can be later expanded to either resolve
>   * the channel in some more dynamic manner, or get the channel as a user
>   * parameter.
>   */
> -static enum omap_channel dsi_get_channel(struct dsi_data *dsi)
> +static enum omap_channel dsi_get_dispc_channel(struct dsi_data *dsi)
>  {
>  	switch (dsi->data->model) {
>  	case DSI_MODEL_OMAP3:
> @@ -4880,14 +4880,14 @@ static enum omap_channel dsi_get_channel(struct dsi_data *dsi)
>  	}
>  }
>  
> -static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
> +static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc,
>  				       const struct mipi_dsi_msg *msg)
>  {
>  	struct omap_dss_device *dssdev = &dsi->output;
>  	int r;
>  
>  	if (!!(msg->flags & MIPI_DSI_MSG_USE_LPM) != dsi->in_lp_mode)
> -		dsi_vc_enable_hs(dssdev, msg->channel,
> +		dsi_vc_enable_hs(dssdev, vc,
>  				 !(msg->flags & MIPI_DSI_MSG_USE_LPM));
>  
>  	switch (msg->type) {
> @@ -4900,15 +4900,15 @@ static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
>  	case MIPI_DSI_DCS_LONG_WRITE:
>  	case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
>  	case MIPI_DSI_NULL_PACKET:
> -		r = dsi_vc_write_common(dssdev, msg);
> +		r = dsi_vc_write_common(dssdev, vc, msg);
>  		break;
>  	case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
>  	case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
>  	case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
> -		r = dsi_vc_generic_read(dssdev, msg);
> +		r = dsi_vc_generic_read(dssdev, vc, msg);
>  		break;
>  	case MIPI_DSI_DCS_READ:
> -		r = dsi_vc_dcs_read(dssdev, msg);
> +		r = dsi_vc_dcs_read(dssdev, vc, msg);
>  		break;
>  	default:
>  		r = -EINVAL;
> @@ -4936,12 +4936,13 @@ static ssize_t omap_dsi_host_transfer(struct mipi_dsi_host *host,
>  {
>  	struct dsi_data *dsi = host_to_omap(host);
>  	int r;
> +	int vc = VC_DEFAULT;
>  
>  	dsi_bus_lock(dsi);
>  
>  	if (dsi->video_enabled) {
>  		dsi_set_ulps_auto(dsi, false);
> -		r = _omap_dsi_host_transfer(dsi, msg);
> +		r = _omap_dsi_host_transfer(dsi, vc, msg);
>  		dsi_set_ulps_auto(dsi, true);
>  	} else {
>  		r = -EIO;
> @@ -5398,7 +5399,7 @@ static int dsi_init_output(struct dsi_data *dsi)
>  
>  	out->type = OMAP_DISPLAY_TYPE_DSI;
>  	out->name = dsi->module_id == 0 ? "dsi.0" : "dsi.1";
> -	out->dispc_channel = dsi_get_channel(dsi);
> +	out->dispc_channel = dsi_get_dispc_channel(dsi);
>  	out->dsi_ops = &dsi_ops;
>  	out->of_port = 0;
>  	out->bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE
Tomi Valkeinen Dec. 1, 2020, 11:23 a.m. UTC | #2
On 01/12/2020 02:17, Laurent Pinchart wrote:
> Hi Tomi,
> 
> Thank you for the patch.
> 
> On Tue, Nov 24, 2020 at 02:45:22PM +0200, Tomi Valkeinen wrote:
>> The "channel" usage in omap dsi driver is super confusing. We have three
>> different "channels":
>>
>> 1) DSI virtual channel ID. This is a number from 0 to 3, included in the
>> packet payload.
>>
>> 2) VC. This is a register block in the DSI IP. There are four of those
>> blocks. A VC is a DSI "pipeline", with defined fifo settings, data
>> source (cpu or dispc), and some other settings. It has no relation to
>> the 1).
> 
> Lovely that it's called VC :-)

Yes. There are 4 VC blocks. My guess is that initially the HW designers meant that one HW VC block
is used for one DSI channel (DSI supports 4 channels). But at least I cannot see how the HW could be
used that way.

>> 3) dispc channel. It's the "pipeline" number dispc uses to send pixel
>> data.
>>
>> To clean this up use the following names for each of the above: 1)
>> "channel" 2) "vc" 3) "dispc_channel"
> 
> 1) and 2) will still be prone to confusion :-S Would it help to name 2)
> hw_vc or something similar ?

The omap dsi driver uses "vc" and "channel" consistently after this patch, and afaics in the DRM
framework it's always "channel". So I kind of agree with you but I hope this is enough. Otherwise
I'll spend lots of hours solving the conflicts after rename... Well, a new rename patch could be
done later on top if needed.

>> This patch is mostly about renaming things, but as in some places 1) and
>> 2) have gotten mixed up, additional changes were needed to untangle
>> them. This is mostly just adding a new parameter to some functions so
>> that we pass both the vc and the channel.
> 
> It would ease review if this could be split in two patches.

Ok. I'll see if I can split this up without a huge amount of work. They are a bit tangled up... But
I agree, this is a bit too big patch.

 Tomi
diff mbox series

Patch

diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c
index fbf05097612f..4ac82166edc3 100644
--- a/drivers/gpu/drm/omapdrm/dss/dsi.c
+++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
@@ -214,9 +214,9 @@  static void dsi_set_ulps_auto(struct dsi_data *dsi, bool enable);
 static int dsi_display_init_dispc(struct dsi_data *dsi);
 static void dsi_display_uninit_dispc(struct dsi_data *dsi);
 
-static int dsi_vc_send_null(struct dsi_data *dsi, int channel);
+static int dsi_vc_send_null(struct dsi_data *dsi, int vc, int channel);
 
-static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
+static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc,
 				       const struct mipi_dsi_msg *msg);
 
 static void dsi_display_disable(struct omap_dss_device *dssdev);
@@ -376,7 +376,7 @@  struct dsi_data {
 	/* space for a copy used by the interrupt handler */
 	struct dsi_isr_tables isr_tables_copy;
 
-	int update_channel;
+	int update_vc;
 #ifdef DSI_PERF_MEASURE
 	unsigned int update_bytes;
 #endif
@@ -639,7 +639,7 @@  static void print_irq_status(u32 status)
 #undef PIS
 }
 
-static void print_irq_status_vc(int channel, u32 status)
+static void print_irq_status_vc(int vc, u32 status)
 {
 	if (status == 0)
 		return;
@@ -650,7 +650,7 @@  static void print_irq_status_vc(int channel, u32 status)
 #define PIS(x) (status & DSI_VC_IRQ_##x) ? (#x " ") : ""
 
 	pr_debug("DSI VC(%d) IRQ 0x%x: %s%s%s%s%s%s%s%s%s\n",
-		channel,
+		vc,
 		status,
 		PIS(CS),
 		PIS(ECC_CORR),
@@ -1031,7 +1031,7 @@  static int dsi_unregister_isr(struct dsi_data *dsi, omap_dsi_isr_t isr,
 	return r;
 }
 
-static int dsi_register_isr_vc(struct dsi_data *dsi, int channel,
+static int dsi_register_isr_vc(struct dsi_data *dsi, int vc,
 			       omap_dsi_isr_t isr, void *arg, u32 mask)
 {
 	unsigned long flags;
@@ -1040,18 +1040,18 @@  static int dsi_register_isr_vc(struct dsi_data *dsi, int channel,
 	spin_lock_irqsave(&dsi->irq_lock, flags);
 
 	r = _dsi_register_isr(isr, arg, mask,
-			dsi->isr_tables.isr_table_vc[channel],
-			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[channel]));
+			dsi->isr_tables.isr_table_vc[vc],
+			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[vc]));
 
 	if (r == 0)
-		_omap_dsi_set_irqs_vc(dsi, channel);
+		_omap_dsi_set_irqs_vc(dsi, vc);
 
 	spin_unlock_irqrestore(&dsi->irq_lock, flags);
 
 	return r;
 }
 
-static int dsi_unregister_isr_vc(struct dsi_data *dsi, int channel,
+static int dsi_unregister_isr_vc(struct dsi_data *dsi, int vc,
 				 omap_dsi_isr_t isr, void *arg, u32 mask)
 {
 	unsigned long flags;
@@ -1060,11 +1060,11 @@  static int dsi_unregister_isr_vc(struct dsi_data *dsi, int channel,
 	spin_lock_irqsave(&dsi->irq_lock, flags);
 
 	r = _dsi_unregister_isr(isr, arg, mask,
-			dsi->isr_tables.isr_table_vc[channel],
-			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[channel]));
+			dsi->isr_tables.isr_table_vc[vc],
+			ARRAY_SIZE(dsi->isr_tables.isr_table_vc[vc]));
 
 	if (r == 0)
-		_omap_dsi_set_irqs_vc(dsi, channel);
+		_omap_dsi_set_irqs_vc(dsi, vc);
 
 	spin_unlock_irqrestore(&dsi->irq_lock, flags);
 
@@ -2232,9 +2232,9 @@  static int dsi_force_tx_stop_mode_io(struct dsi_data *dsi)
 	return 0;
 }
 
-static bool dsi_vc_is_enabled(struct dsi_data *dsi, int channel)
+static bool dsi_vc_is_enabled(struct dsi_data *dsi, int vc)
 {
-	return REG_GET(dsi, DSI_VC_CTRL(channel), 0, 0);
+	return REG_GET(dsi, DSI_VC_CTRL(vc), 0, 0);
 }
 
 static void dsi_packet_sent_handler_vp(void *data, u32 mask)
@@ -2242,14 +2242,14 @@  static void dsi_packet_sent_handler_vp(void *data, u32 mask)
 	struct dsi_packet_sent_handler_data *vp_data =
 		(struct dsi_packet_sent_handler_data *) data;
 	struct dsi_data *dsi = vp_data->dsi;
-	const int channel = dsi->update_channel;
+	const int vc = dsi->update_vc;
 	u8 bit = dsi->te_enabled ? 30 : 31;
 
-	if (REG_GET(dsi, DSI_VC_TE(channel), bit, bit) == 0)
+	if (REG_GET(dsi, DSI_VC_TE(vc), bit, bit) == 0)
 		complete(vp_data->completion);
 }
 
-static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
+static int dsi_sync_vc_vp(struct dsi_data *dsi, int vc)
 {
 	DECLARE_COMPLETION_ONSTACK(completion);
 	struct dsi_packet_sent_handler_data vp_data = {
@@ -2261,13 +2261,13 @@  static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
 
 	bit = dsi->te_enabled ? 30 : 31;
 
-	r = dsi_register_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
+	r = dsi_register_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
 		&vp_data, DSI_VC_IRQ_PACKET_SENT);
 	if (r)
 		goto err0;
 
 	/* Wait for completion only if TE_EN/TE_START is still set */
-	if (REG_GET(dsi, DSI_VC_TE(channel), bit, bit)) {
+	if (REG_GET(dsi, DSI_VC_TE(vc), bit, bit)) {
 		if (wait_for_completion_timeout(&completion,
 				msecs_to_jiffies(10)) == 0) {
 			DSSERR("Failed to complete previous frame transfer\n");
@@ -2276,12 +2276,12 @@  static int dsi_sync_vc_vp(struct dsi_data *dsi, int channel)
 		}
 	}
 
-	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
+	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
 		&vp_data, DSI_VC_IRQ_PACKET_SENT);
 
 	return 0;
 err1:
-	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_vp,
+	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_vp,
 		&vp_data, DSI_VC_IRQ_PACKET_SENT);
 err0:
 	return r;
@@ -2292,13 +2292,13 @@  static void dsi_packet_sent_handler_l4(void *data, u32 mask)
 	struct dsi_packet_sent_handler_data *l4_data =
 		(struct dsi_packet_sent_handler_data *) data;
 	struct dsi_data *dsi = l4_data->dsi;
-	const int channel = dsi->update_channel;
+	const int vc = dsi->update_vc;
 
-	if (REG_GET(dsi, DSI_VC_CTRL(channel), 5, 5) == 0)
+	if (REG_GET(dsi, DSI_VC_CTRL(vc), 5, 5) == 0)
 		complete(l4_data->completion);
 }
 
-static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
+static int dsi_sync_vc_l4(struct dsi_data *dsi, int vc)
 {
 	DECLARE_COMPLETION_ONSTACK(completion);
 	struct dsi_packet_sent_handler_data l4_data = {
@@ -2307,13 +2307,13 @@  static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
 	};
 	int r = 0;
 
-	r = dsi_register_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
+	r = dsi_register_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
 		&l4_data, DSI_VC_IRQ_PACKET_SENT);
 	if (r)
 		goto err0;
 
 	/* Wait for completion only if TX_FIFO_NOT_EMPTY is still set */
-	if (REG_GET(dsi, DSI_VC_CTRL(channel), 5, 5)) {
+	if (REG_GET(dsi, DSI_VC_CTRL(vc), 5, 5)) {
 		if (wait_for_completion_timeout(&completion,
 				msecs_to_jiffies(10)) == 0) {
 			DSSERR("Failed to complete previous l4 transfer\n");
@@ -2322,47 +2322,47 @@  static int dsi_sync_vc_l4(struct dsi_data *dsi, int channel)
 		}
 	}
 
-	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
+	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
 		&l4_data, DSI_VC_IRQ_PACKET_SENT);
 
 	return 0;
 err1:
-	dsi_unregister_isr_vc(dsi, channel, dsi_packet_sent_handler_l4,
+	dsi_unregister_isr_vc(dsi, vc, dsi_packet_sent_handler_l4,
 		&l4_data, DSI_VC_IRQ_PACKET_SENT);
 err0:
 	return r;
 }
 
-static int dsi_sync_vc(struct dsi_data *dsi, int channel)
+static int dsi_sync_vc(struct dsi_data *dsi, int vc)
 {
 	WARN_ON(!dsi_bus_is_locked(dsi));
 
 	WARN_ON(in_interrupt());
 
-	if (!dsi_vc_is_enabled(dsi, channel))
+	if (!dsi_vc_is_enabled(dsi, vc))
 		return 0;
 
-	switch (dsi->vc[channel].source) {
+	switch (dsi->vc[vc].source) {
 	case DSI_VC_SOURCE_VP:
-		return dsi_sync_vc_vp(dsi, channel);
+		return dsi_sync_vc_vp(dsi, vc);
 	case DSI_VC_SOURCE_L4:
-		return dsi_sync_vc_l4(dsi, channel);
+		return dsi_sync_vc_l4(dsi, vc);
 	default:
 		BUG();
 		return -EINVAL;
 	}
 }
 
-static int dsi_vc_enable(struct dsi_data *dsi, int channel, bool enable)
+static int dsi_vc_enable(struct dsi_data *dsi, int vc, bool enable)
 {
-	DSSDBG("dsi_vc_enable channel %d, enable %d\n",
-			channel, enable);
+	DSSDBG("dsi_vc_enable vc %d, enable %d\n",
+			vc, enable);
 
 	enable = enable ? 1 : 0;
 
-	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 0, 0);
+	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 0, 0);
 
-	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(channel), 0, enable)) {
+	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(vc), 0, enable)) {
 		DSSERR("Failed to set dsi_vc_enable to %d\n", enable);
 		return -EIO;
 	}
@@ -2370,17 +2370,17 @@  static int dsi_vc_enable(struct dsi_data *dsi, int channel, bool enable)
 	return 0;
 }
 
-static void dsi_vc_initial_config(struct dsi_data *dsi, int channel)
+static void dsi_vc_initial_config(struct dsi_data *dsi, int vc)
 {
 	u32 r;
 
-	DSSDBG("Initial config of virtual channel %d", channel);
+	DSSDBG("Initial config of VC %d", vc);
 
-	r = dsi_read_reg(dsi, DSI_VC_CTRL(channel));
+	r = dsi_read_reg(dsi, DSI_VC_CTRL(vc));
 
 	if (FLD_GET(r, 15, 15)) /* VC_BUSY */
 		DSSERR("VC(%d) busy when trying to configure it!\n",
-				channel);
+				vc);
 
 	r = FLD_MOD(r, 0, 1, 1); /* SOURCE, 0 = L4 */
 	r = FLD_MOD(r, 0, 2, 2); /* BTA_SHORT_EN  */
@@ -2395,76 +2395,76 @@  static void dsi_vc_initial_config(struct dsi_data *dsi, int channel)
 	r = FLD_MOD(r, 4, 29, 27); /* DMA_RX_REQ_NB = no dma */
 	r = FLD_MOD(r, 4, 23, 21); /* DMA_TX_REQ_NB = no dma */
 
-	dsi_write_reg(dsi, DSI_VC_CTRL(channel), r);
+	dsi_write_reg(dsi, DSI_VC_CTRL(vc), r);
 
-	dsi->vc[channel].source = DSI_VC_SOURCE_L4;
+	dsi->vc[vc].source = DSI_VC_SOURCE_L4;
 }
 
-static int dsi_vc_config_source(struct dsi_data *dsi, int channel,
+static int dsi_vc_config_source(struct dsi_data *dsi, int vc,
 				enum dsi_vc_source source)
 {
-	if (dsi->vc[channel].source == source)
+	if (dsi->vc[vc].source == source)
 		return 0;
 
-	DSSDBG("Source config of virtual channel %d", channel);
+	DSSDBG("Source config of VC %d", vc);
 
-	dsi_sync_vc(dsi, channel);
+	dsi_sync_vc(dsi, vc);
 
-	dsi_vc_enable(dsi, channel, 0);
+	dsi_vc_enable(dsi, vc, 0);
 
 	/* VC_BUSY */
-	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(channel), 15, 0)) {
-		DSSERR("vc(%d) busy when trying to config for VP\n", channel);
+	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(vc), 15, 0)) {
+		DSSERR("vc(%d) busy when trying to config for VP\n", vc);
 		return -EIO;
 	}
 
 	/* SOURCE, 0 = L4, 1 = video port */
-	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), source, 1, 1);
+	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), source, 1, 1);
 
 	/* DCS_CMD_ENABLE */
 	if (dsi->data->quirks & DSI_QUIRK_DCS_CMD_CONFIG_VC) {
 		bool enable = source == DSI_VC_SOURCE_VP;
-		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 30, 30);
+		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 30, 30);
 	}
 
-	dsi_vc_enable(dsi, channel, 1);
+	dsi_vc_enable(dsi, vc, 1);
 
-	dsi->vc[channel].source = source;
+	dsi->vc[vc].source = source;
 
 	return 0;
 }
 
-static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int channel,
+static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
 		bool enable)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 
-	DSSDBG("dsi_vc_enable_hs(%d, %d)\n", channel, enable);
+	DSSDBG("dsi_vc_enable_hs(%d, %d)\n", vc, enable);
 
 	WARN_ON(!dsi_bus_is_locked(dsi));
 
-	dsi_vc_enable(dsi, channel, 0);
+	dsi_vc_enable(dsi, vc, 0);
 	dsi_if_enable(dsi, 0);
 
-	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), enable, 9, 9);
+	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 9, 9);
 
-	dsi_vc_enable(dsi, channel, 1);
+	dsi_vc_enable(dsi, vc, 1);
 	dsi_if_enable(dsi, 1);
 
 	dsi_force_tx_stop_mode_io(dsi);
 
 	/* start the DDR clock by sending a NULL packet */
 	if (dsi->vm_timings.ddr_clk_always_on && enable)
-		dsi_vc_send_null(dsi, channel);
+		dsi_vc_send_null(dsi, vc, dsi->dsidev->channel);
 
 	dsi->in_lp_mode = !enable;
 }
 
-static void dsi_vc_flush_long_data(struct dsi_data *dsi, int channel)
+static void dsi_vc_flush_long_data(struct dsi_data *dsi, int vc)
 {
-	while (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
+	while (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
 		u32 val;
-		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
+		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
 		DSSDBG("\t\tb1 %#02x b2 %#02x b3 %#02x b4 %#02x\n",
 				(val >> 0) & 0xff,
 				(val >> 8) & 0xff,
@@ -2510,13 +2510,13 @@  static void dsi_show_rx_ack_with_err(u16 err)
 		DSSERR("\t\tDSI Protocol Violation\n");
 }
 
-static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
+static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int vc)
 {
 	/* RX_FIFO_NOT_EMPTY */
-	while (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
+	while (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
 		u32 val;
 		u8 dt;
-		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
+		val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
 		DSSERR("\trawval %#08x\n", val);
 		dt = FLD_GET(val, 5, 0);
 		if (dt == MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT) {
@@ -2531,7 +2531,7 @@  static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
 		} else if (dt == MIPI_DSI_RX_DCS_LONG_READ_RESPONSE) {
 			DSSERR("\tDCS long response, len %d\n",
 					FLD_GET(val, 23, 8));
-			dsi_vc_flush_long_data(dsi, channel);
+			dsi_vc_flush_long_data(dsi, vc);
 		} else {
 			DSSERR("\tunknown datatype 0x%02x\n", dt);
 		}
@@ -2539,35 +2539,35 @@  static u16 dsi_vc_flush_receive_data(struct dsi_data *dsi, int channel)
 	return 0;
 }
 
-static int dsi_vc_send_bta(struct dsi_data *dsi, int channel)
+static int dsi_vc_send_bta(struct dsi_data *dsi, int vc)
 {
 	if (dsi->debug_write || dsi->debug_read)
-		DSSDBG("dsi_vc_send_bta %d\n", channel);
+		DSSDBG("dsi_vc_send_bta %d\n", vc);
 
 	WARN_ON(!dsi_bus_is_locked(dsi));
 
 	/* RX_FIFO_NOT_EMPTY */
-	if (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20)) {
+	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
 		DSSERR("rx fifo not empty when sending BTA, dumping data:\n");
-		dsi_vc_flush_receive_data(dsi, channel);
+		dsi_vc_flush_receive_data(dsi, vc);
 	}
 
-	REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 1, 6, 6); /* BTA_EN */
+	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 1, 6, 6); /* BTA_EN */
 
 	/* flush posted write */
-	dsi_read_reg(dsi, DSI_VC_CTRL(channel));
+	dsi_read_reg(dsi, DSI_VC_CTRL(vc));
 
 	return 0;
 }
 
-static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
+static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int vc)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	DECLARE_COMPLETION_ONSTACK(completion);
 	int r = 0;
 	u32 err;
 
-	r = dsi_register_isr_vc(dsi, channel, dsi_completion_handler,
+	r = dsi_register_isr_vc(dsi, vc, dsi_completion_handler,
 			&completion, DSI_VC_IRQ_BTA);
 	if (r)
 		goto err0;
@@ -2577,7 +2577,7 @@  static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
 	if (r)
 		goto err1;
 
-	r = dsi_vc_send_bta(dsi, channel);
+	r = dsi_vc_send_bta(dsi, vc);
 	if (r)
 		goto err2;
 
@@ -2598,14 +2598,15 @@  static int dsi_vc_send_bta_sync(struct omap_dss_device *dssdev, int channel)
 	dsi_unregister_isr(dsi, dsi_completion_handler, &completion,
 			DSI_IRQ_ERROR_MASK);
 err1:
-	dsi_unregister_isr_vc(dsi, channel, dsi_completion_handler,
+	dsi_unregister_isr_vc(dsi, vc, dsi_completion_handler,
 			&completion, DSI_VC_IRQ_BTA);
 err0:
 	return r;
 }
 
-static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int channel,
-					    u8 data_type, u16 len, u8 ecc)
+static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int vc,
+					    int channel, u8 data_type, u16 len,
+					    u8 ecc)
 {
 	u32 val;
 	u8 data_id;
@@ -2615,12 +2616,12 @@  static inline void dsi_vc_write_long_header(struct dsi_data *dsi, int channel,
 	data_id = data_type | channel << 6;
 
 	val = FLD_VAL(data_id, 7, 0) | FLD_VAL(len, 23, 8) |
-		FLD_VAL(ecc, 31, 24);
+	      FLD_VAL(ecc, 31, 24);
 
-	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_HEADER(channel), val);
+	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_HEADER(vc), val);
 }
 
-static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int channel,
+static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int vc,
 					     u8 b1, u8 b2, u8 b3, u8 b4)
 {
 	u32 val;
@@ -2630,10 +2631,10 @@  static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int channel,
 /*	DSSDBG("\twriting %02x, %02x, %02x, %02x (%#010x)\n",
 			b1, b2, b3, b4, val); */
 
-	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_PAYLOAD(channel), val);
+	dsi_write_reg(dsi, DSI_VC_LONG_PACKET_PAYLOAD(vc), val);
 }
 
-static int dsi_vc_send_long(struct dsi_data *dsi,
+static int dsi_vc_send_long(struct dsi_data *dsi, int vc,
 			    const struct mipi_dsi_msg *msg)
 {
 	/*u32 val; */
@@ -2646,14 +2647,14 @@  static int dsi_vc_send_long(struct dsi_data *dsi,
 		DSSDBG("dsi_vc_send_long, %d bytes\n", msg->tx_len);
 
 	/* len + header */
-	if (dsi->vc[msg->channel].tx_fifo_size * 32 * 4 < msg->tx_len + 4) {
+	if (dsi->vc[vc].tx_fifo_size * 32 * 4 < msg->tx_len + 4) {
 		DSSERR("unable to send long packet: packet too long.\n");
 		return -EINVAL;
 	}
 
-	dsi_vc_config_source(dsi, msg->channel, DSI_VC_SOURCE_L4);
+	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
 
-	dsi_vc_write_long_header(dsi, msg->channel, msg->type, msg->tx_len, 0);
+	dsi_vc_write_long_header(dsi, vc, msg->channel, msg->type, msg->tx_len, 0);
 
 	p = msg->tx_buf;
 	for (i = 0; i < msg->tx_len >> 2; i++) {
@@ -2665,7 +2666,7 @@  static int dsi_vc_send_long(struct dsi_data *dsi,
 		b3 = *p++;
 		b4 = *p++;
 
-		dsi_vc_write_long_payload(dsi, msg->channel, b1, b2, b3, b4);
+		dsi_vc_write_long_payload(dsi, vc, b1, b2, b3, b4);
 	}
 
 	i = msg->tx_len % 4;
@@ -2690,13 +2691,13 @@  static int dsi_vc_send_long(struct dsi_data *dsi,
 			break;
 		}
 
-		dsi_vc_write_long_payload(dsi, msg->channel, b1, b2, b3, 0);
+		dsi_vc_write_long_payload(dsi, vc, b1, b2, b3, 0);
 	}
 
 	return r;
 }
 
-static int dsi_vc_send_short(struct dsi_data *dsi,
+static int dsi_vc_send_short(struct dsi_data *dsi, int vc,
 			     const struct mipi_dsi_msg *msg)
 {
 	struct mipi_dsi_packet pkt;
@@ -2710,11 +2711,11 @@  static int dsi_vc_send_short(struct dsi_data *dsi,
 
 	if (dsi->debug_write)
 		DSSDBG("dsi_vc_send_short(ch%d, dt %#x, b1 %#x, b2 %#x)\n",
-		       msg->channel, msg->type, pkt.header[1], pkt.header[2]);
+		       vc, msg->type, pkt.header[1], pkt.header[2]);
 
-	dsi_vc_config_source(dsi, msg->channel, DSI_VC_SOURCE_L4);
+	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
 
-	if (FLD_GET(dsi_read_reg(dsi, DSI_VC_CTRL(msg->channel)), 16, 16)) {
+	if (FLD_GET(dsi_read_reg(dsi, DSI_VC_CTRL(vc)), 16, 16)) {
 		DSSERR("ERROR FIFO FULL, aborting transfer\n");
 		return -EINVAL;
 	}
@@ -2722,31 +2723,31 @@  static int dsi_vc_send_short(struct dsi_data *dsi,
 	r = pkt.header[3] << 24 | pkt.header[2] << 16 | pkt.header[1] << 8 |
 	    pkt.header[0];
 
-	dsi_write_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(msg->channel), r);
+	dsi_write_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc), r);
 
 	return 0;
 }
 
-static int dsi_vc_send_null(struct dsi_data *dsi, int channel)
+static int dsi_vc_send_null(struct dsi_data *dsi, int vc, int channel)
 {
 	const struct mipi_dsi_msg msg = {
 		.channel = channel,
 		.type = MIPI_DSI_NULL_PACKET,
 	};
 
-	return dsi_vc_send_long(dsi, &msg);
+	return dsi_vc_send_long(dsi, vc, &msg);
 }
 
-static int dsi_vc_write_common(struct omap_dss_device *dssdev,
+static int dsi_vc_write_common(struct omap_dss_device *dssdev, int vc,
 			       const struct mipi_dsi_msg *msg)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	int r;
 
 	if (mipi_dsi_packet_format_is_short(msg->type))
-		r = dsi_vc_send_short(dsi, msg);
+		r = dsi_vc_send_short(dsi, vc, msg);
 	else
-		r = dsi_vc_send_long(dsi, msg);
+		r = dsi_vc_send_long(dsi, vc, msg);
 
 	if (r < 0)
 		return r;
@@ -2758,23 +2759,23 @@  static int dsi_vc_write_common(struct omap_dss_device *dssdev,
 	 * In that case we can return early.
 	 */
 
-	r = dsi_vc_send_bta_sync(dssdev, msg->channel);
+	r = dsi_vc_send_bta_sync(dssdev, vc);
 	if (r) {
 		DSSERR("bta sync failed\n");
 		return r;
 	}
 
 	/* RX_FIFO_NOT_EMPTY */
-	if (REG_GET(dsi, DSI_VC_CTRL(msg->channel), 20, 20)) {
+	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20)) {
 		DSSERR("rx fifo not empty after write, dumping data:\n");
-		dsi_vc_flush_receive_data(dsi, msg->channel);
+		dsi_vc_flush_receive_data(dsi, vc);
 		return -EIO;
 	}
 
 	return 0;
 }
 
-static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
+static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int vc, u8 *buf,
 			       int buflen, enum dss_dsi_content_type type)
 {
 	u32 val;
@@ -2782,13 +2783,13 @@  static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
 	int r;
 
 	/* RX_FIFO_NOT_EMPTY */
-	if (REG_GET(dsi, DSI_VC_CTRL(channel), 20, 20) == 0) {
+	if (REG_GET(dsi, DSI_VC_CTRL(vc), 20, 20) == 0) {
 		DSSERR("RX fifo empty when trying to read.\n");
 		r = -EIO;
 		goto err;
 	}
 
-	val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(channel));
+	val = dsi_read_reg(dsi, DSI_VC_SHORT_PACKET_HEADER(vc));
 	if (dsi->debug_read)
 		DSSDBG("\theader: %08x\n", val);
 	dt = FLD_GET(val, 5, 0);
@@ -2852,7 +2853,7 @@  static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
 		for (w = 0; w < len + 2;) {
 			int b;
 			val = dsi_read_reg(dsi,
-				DSI_VC_SHORT_PACKET_HEADER(channel));
+				DSI_VC_SHORT_PACKET_HEADER(vc));
 			if (dsi->debug_read)
 				DSSDBG("\t\t%02x %02x %02x %02x\n",
 						(val >> 0) & 0xff,
@@ -2876,32 +2877,31 @@  static int dsi_vc_read_rx_fifo(struct dsi_data *dsi, int channel, u8 *buf,
 	}
 
 err:
-	DSSERR("dsi_vc_read_rx_fifo(ch %d type %s) failed\n", channel,
+	DSSERR("dsi_vc_read_rx_fifo(vc %d type %s) failed\n", vc,
 		type == DSS_DSI_CONTENT_GENERIC ? "GENERIC" : "DCS");
 
 	return r;
 }
 
-static int dsi_vc_dcs_read(struct omap_dss_device *dssdev,
+static int dsi_vc_dcs_read(struct omap_dss_device *dssdev, int vc,
 			   const struct mipi_dsi_msg *msg)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	u8 cmd = ((u8 *)msg->tx_buf)[0];
-	u8 channel = msg->channel;
 	int r;
 
 	if (dsi->debug_read)
-		DSSDBG("%s(ch %d, cmd %x)\n", __func__, channel, cmd);
+		DSSDBG("%s(ch %d, cmd %x)\n", __func__, vc, cmd);
 
-	r = dsi_vc_send_short(dsi, msg);
+	r = dsi_vc_send_short(dsi, vc, msg);
 	if (r)
 		goto err;
 
-	r = dsi_vc_send_bta_sync(dssdev, channel);
+	r = dsi_vc_send_bta_sync(dssdev, vc);
 	if (r)
 		goto err;
 
-	r = dsi_vc_read_rx_fifo(dsi, channel, msg->rx_buf, msg->rx_len,
+	r = dsi_vc_read_rx_fifo(dsi, vc, msg->rx_buf, msg->rx_len,
 		DSS_DSI_CONTENT_DCS);
 	if (r < 0)
 		goto err;
@@ -2913,25 +2913,25 @@  static int dsi_vc_dcs_read(struct omap_dss_device *dssdev,
 
 	return 0;
 err:
-	DSSERR("%s(ch %d, cmd 0x%02x) failed\n", __func__,  msg->channel, cmd);
+	DSSERR("%s(ch %d, cmd 0x%02x) failed\n", __func__,  vc, cmd);
 	return r;
 }
 
-static int dsi_vc_generic_read(struct omap_dss_device *dssdev,
+static int dsi_vc_generic_read(struct omap_dss_device *dssdev, int vc,
 			       const struct mipi_dsi_msg *msg)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	int r;
 
-	r = dsi_vc_send_short(dsi, msg);
+	r = dsi_vc_send_short(dsi, vc, msg);
 	if (r)
 		goto err;
 
-	r = dsi_vc_send_bta_sync(dssdev, msg->channel);
+	r = dsi_vc_send_bta_sync(dssdev, vc);
 	if (r)
 		goto err;
 
-	r = dsi_vc_read_rx_fifo(dsi, msg->channel, msg->rx_buf, msg->rx_len,
+	r = dsi_vc_read_rx_fifo(dsi, vc, msg->rx_buf, msg->rx_len,
 		DSS_DSI_CONTENT_GENERIC);
 	if (r < 0)
 		goto err;
@@ -2943,7 +2943,7 @@  static int dsi_vc_generic_read(struct omap_dss_device *dssdev,
 
 	return 0;
 err:
-	DSSERR("%s(ch %d, reqlen %d) failed\n", __func__,  msg->channel, msg->tx_len);
+	DSSERR("%s(ch %d, reqlen %d) failed\n", __func__,  vc, msg->tx_len);
 	return r;
 }
 
@@ -3631,7 +3631,7 @@  static int dsi_configure_pins(struct dsi_data *dsi,
 	return 0;
 }
 
-static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
+static void dsi_enable_video_output(struct omap_dss_device *dssdev, int vc)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	int bpp = mipi_dsi_pixel_format_to_bpp(dsi->pix_fmt);
@@ -3665,17 +3665,17 @@  static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
 		}
 
 		dsi_if_enable(dsi, false);
-		dsi_vc_enable(dsi, channel, false);
+		dsi_vc_enable(dsi, vc, false);
 
 		/* MODE, 1 = video mode */
-		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 1, 4, 4);
+		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 1, 4, 4);
 
 		word_count = DIV_ROUND_UP(dsi->vm.hactive * bpp, 8);
 
-		dsi_vc_write_long_header(dsi, channel, data_type,
+		dsi_vc_write_long_header(dsi, vc, dsi->dsidev->channel, data_type,
 				word_count, 0);
 
-		dsi_vc_enable(dsi, channel, true);
+		dsi_vc_enable(dsi, vc, true);
 		dsi_if_enable(dsi, true);
 	}
 
@@ -3688,7 +3688,7 @@  static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
 err_mgr_enable:
 	if (dsi->mode == OMAP_DSS_DSI_VIDEO_MODE) {
 		dsi_if_enable(dsi, false);
-		dsi_vc_enable(dsi, channel, false);
+		dsi_vc_enable(dsi, vc, false);
 	}
 err_pix_fmt:
 	dsi_display_uninit_dispc(dsi);
@@ -3696,18 +3696,18 @@  static void dsi_enable_video_output(struct omap_dss_device *dssdev, int channel)
 	return;
 }
 
-static void dsi_disable_video_output(struct omap_dss_device *dssdev, int channel)
+static void dsi_disable_video_output(struct omap_dss_device *dssdev, int vc)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 
 	if (dsi->mode == OMAP_DSS_DSI_VIDEO_MODE) {
 		dsi_if_enable(dsi, false);
-		dsi_vc_enable(dsi, channel, false);
+		dsi_vc_enable(dsi, vc, false);
 
 		/* MODE, 0 = command mode */
-		REG_FLD_MOD(dsi, DSI_VC_CTRL(channel), 0, 4, 4);
+		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), 0, 4, 4);
 
-		dsi_vc_enable(dsi, channel, true);
+		dsi_vc_enable(dsi, vc, true);
 		dsi_if_enable(dsi, true);
 	}
 
@@ -3740,14 +3740,14 @@  static void dsi_update_screen_dispc(struct dsi_data *dsi)
 	unsigned int packet_len;
 	u32 l;
 	int r;
-	const unsigned channel = dsi->update_channel;
+	const unsigned vc = dsi->update_vc;
 	const unsigned int line_buf_size = dsi->line_buffer_size;
 	u16 w = dsi->vm.hactive;
 	u16 h = dsi->vm.vactive;
 
 	DSSDBG("dsi_update_screen_dispc(%dx%d)\n", w, h);
 
-	dsi_vc_config_source(dsi, channel, DSI_VC_SOURCE_VP);
+	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_VP);
 
 	bytespp	= mipi_dsi_pixel_format_to_bpp(dsi->pix_fmt) / 8;
 	bytespl = w * bytespp;
@@ -3768,16 +3768,16 @@  static void dsi_update_screen_dispc(struct dsi_data *dsi)
 		total_len += (bytespf % packet_payload) + 1;
 
 	l = FLD_VAL(total_len, 23, 0); /* TE_SIZE */
-	dsi_write_reg(dsi, DSI_VC_TE(channel), l);
+	dsi_write_reg(dsi, DSI_VC_TE(vc), l);
 
-	dsi_vc_write_long_header(dsi, channel, MIPI_DSI_DCS_LONG_WRITE,
+	dsi_vc_write_long_header(dsi, vc, dsi->dsidev->channel, MIPI_DSI_DCS_LONG_WRITE,
 		packet_len, 0);
 
 	if (dsi->te_enabled)
 		l = FLD_MOD(l, 1, 30, 30); /* TE_EN */
 	else
 		l = FLD_MOD(l, 1, 31, 31); /* TE_START */
-	dsi_write_reg(dsi, DSI_VC_TE(channel), l);
+	dsi_write_reg(dsi, DSI_VC_TE(vc), l);
 
 	/* We put SIDLEMODE to no-idle for the duration of the transfer,
 	 * because DSS interrupts are not capable of waking up the CPU and the
@@ -3800,7 +3800,7 @@  static void dsi_update_screen_dispc(struct dsi_data *dsi)
 		 * for TE is longer than the timer allows */
 		REG_FLD_MOD(dsi, DSI_TIMING2, 0, 15, 15); /* LP_RX_TO */
 
-		dsi_vc_send_bta(dsi, channel);
+		dsi_vc_send_bta(dsi, vc);
 
 #ifdef DSI_CATCH_MISSING_TE
 		mod_timer(&dsi->te_timer, jiffies + msecs_to_jiffies(250));
@@ -3882,7 +3882,7 @@  static int _dsi_update(struct dsi_data *dsi)
 	return 0;
 }
 
-static int _dsi_send_nop(struct dsi_data *dsi, int channel)
+static int _dsi_send_nop(struct dsi_data *dsi, int vc, int channel)
 {
 	const u8 payload[] = { MIPI_DCS_NOP };
 	const struct mipi_dsi_msg msg = {
@@ -3894,10 +3894,10 @@  static int _dsi_send_nop(struct dsi_data *dsi, int channel)
 
 	WARN_ON(!dsi_bus_is_locked(dsi));
 
-	return _omap_dsi_host_transfer(dsi, &msg);
+	return _omap_dsi_host_transfer(dsi, vc, &msg);
 }
 
-static int dsi_update_channel(struct omap_dss_device *dssdev, int channel)
+static int dsi_update_channel(struct omap_dss_device *dssdev, int vc)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	int r;
@@ -3914,17 +3914,17 @@  static int dsi_update_channel(struct omap_dss_device *dssdev, int channel)
 		goto err;
 	}
 
-	DSSDBG("dsi_update_channel: %d", channel);
+	DSSDBG("dsi_update_channel: %d", vc);
 
 	dsi_set_ulps_auto(dsi, false);
 
-	r = _dsi_send_nop(dsi, channel);
+	r = _dsi_send_nop(dsi, vc, dsi->dsidev->channel);
 	if (r < 0) {
 		DSSWARN("failed to send nop between frames: %d\n", r);
 		goto err;
 	}
 
-	dsi->update_channel = channel;
+	dsi->update_vc = vc;
 
 	if (dsi->te_enabled && dsi->te_gpio) {
 		schedule_delayed_work(&dsi->te_timeout_work,
@@ -3973,10 +3973,10 @@  static int dsi_configure_dispc_clocks(struct dsi_data *dsi)
 
 static int dsi_display_init_dispc(struct dsi_data *dsi)
 {
-	enum omap_channel channel = dsi->output.dispc_channel;
+	enum omap_channel dispc_channel = dsi->output.dispc_channel;
 	int r;
 
-	dss_select_lcd_clk_source(dsi->dss, channel, dsi->module_id == 0 ?
+	dss_select_lcd_clk_source(dsi->dss, dispc_channel, dsi->module_id == 0 ?
 			DSS_CLK_SRC_PLL1_1 :
 			DSS_CLK_SRC_PLL2_1);
 
@@ -4012,19 +4012,19 @@  static int dsi_display_init_dispc(struct dsi_data *dsi)
 		dss_mgr_unregister_framedone_handler(&dsi->output,
 				dsi_framedone_irq_callback, dsi);
 err:
-	dss_select_lcd_clk_source(dsi->dss, channel, DSS_CLK_SRC_FCK);
+	dss_select_lcd_clk_source(dsi->dss, dispc_channel, DSS_CLK_SRC_FCK);
 	return r;
 }
 
 static void dsi_display_uninit_dispc(struct dsi_data *dsi)
 {
-	enum omap_channel channel = dsi->output.dispc_channel;
+	enum omap_channel dispc_channel = dsi->output.dispc_channel;
 
 	if (dsi->mode == OMAP_DSS_DSI_CMD_MODE)
 		dss_mgr_unregister_framedone_handler(&dsi->output,
 				dsi_framedone_irq_callback, dsi);
 
-	dss_select_lcd_clk_source(dsi->dss, channel, DSS_CLK_SRC_FCK);
+	dss_select_lcd_clk_source(dsi->dss, dispc_channel, DSS_CLK_SRC_FCK);
 }
 
 static int dsi_configure_dsi_clocks(struct dsi_data *dsi)
@@ -4841,12 +4841,12 @@  static int dsi_set_config(struct omap_dss_device *dssdev,
 }
 
 /*
- * Return a hardcoded channel for the DSI output. This should work for
+ * Return a hardcoded dispc channel for the DSI output. This should work for
  * current use cases, but this can be later expanded to either resolve
  * the channel in some more dynamic manner, or get the channel as a user
  * parameter.
  */
-static enum omap_channel dsi_get_channel(struct dsi_data *dsi)
+static enum omap_channel dsi_get_dispc_channel(struct dsi_data *dsi)
 {
 	switch (dsi->data->model) {
 	case DSI_MODEL_OMAP3:
@@ -4880,14 +4880,14 @@  static enum omap_channel dsi_get_channel(struct dsi_data *dsi)
 	}
 }
 
-static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
+static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi, int vc,
 				       const struct mipi_dsi_msg *msg)
 {
 	struct omap_dss_device *dssdev = &dsi->output;
 	int r;
 
 	if (!!(msg->flags & MIPI_DSI_MSG_USE_LPM) != dsi->in_lp_mode)
-		dsi_vc_enable_hs(dssdev, msg->channel,
+		dsi_vc_enable_hs(dssdev, vc,
 				 !(msg->flags & MIPI_DSI_MSG_USE_LPM));
 
 	switch (msg->type) {
@@ -4900,15 +4900,15 @@  static ssize_t _omap_dsi_host_transfer(struct dsi_data *dsi,
 	case MIPI_DSI_DCS_LONG_WRITE:
 	case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
 	case MIPI_DSI_NULL_PACKET:
-		r = dsi_vc_write_common(dssdev, msg);
+		r = dsi_vc_write_common(dssdev, vc, msg);
 		break;
 	case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
 	case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
 	case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
-		r = dsi_vc_generic_read(dssdev, msg);
+		r = dsi_vc_generic_read(dssdev, vc, msg);
 		break;
 	case MIPI_DSI_DCS_READ:
-		r = dsi_vc_dcs_read(dssdev, msg);
+		r = dsi_vc_dcs_read(dssdev, vc, msg);
 		break;
 	default:
 		r = -EINVAL;
@@ -4936,12 +4936,13 @@  static ssize_t omap_dsi_host_transfer(struct mipi_dsi_host *host,
 {
 	struct dsi_data *dsi = host_to_omap(host);
 	int r;
+	int vc = VC_DEFAULT;
 
 	dsi_bus_lock(dsi);
 
 	if (dsi->video_enabled) {
 		dsi_set_ulps_auto(dsi, false);
-		r = _omap_dsi_host_transfer(dsi, msg);
+		r = _omap_dsi_host_transfer(dsi, vc, msg);
 		dsi_set_ulps_auto(dsi, true);
 	} else {
 		r = -EIO;
@@ -5398,7 +5399,7 @@  static int dsi_init_output(struct dsi_data *dsi)
 
 	out->type = OMAP_DISPLAY_TYPE_DSI;
 	out->name = dsi->module_id == 0 ? "dsi.0" : "dsi.1";
-	out->dispc_channel = dsi_get_channel(dsi);
+	out->dispc_channel = dsi_get_dispc_channel(dsi);
 	out->dsi_ops = &dsi_ops;
 	out->of_port = 0;
 	out->bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE