diff mbox series

drm/i915/dsi: Parse the I2C element from the VBT MIPI sequence block (v3)

Message ID 20200110181123.14536-1-vivek.kasireddy@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915/dsi: Parse the I2C element from the VBT MIPI sequence block (v3) | expand

Commit Message

Kasireddy, Vivek Jan. 10, 2020, 6:11 p.m. UTC
Parsing the i2c element is mainly done to transfer the payload from the
MIPI sequence block to the relevant slave device. In some cases, the
commands that are part of the payload can be used to turn on the backlight.

This patch is actually a refactored version of this old patch:
https://lists.freedesktop.org/archives/intel-gfx/2014-December/056897.html

In addition to the refactoring, the original patch is augmented by looking up
the i2c bus from ACPI NS instead of relying on the bus number provided
in the VBT.

This patch was tested on Aava Mobile's Inari 10 tablet. It enabled
turning on the backlight by transfering the payload to the device.

v2:
- Add DRM_DEV_ERROR for invalid adapter and failed transfer and also
  drop the DRM_DEBUG that existed originally. (Hans)
- Add two gotos instead of one to clean things up properly.

v3:
- Identify the device on which this patch was tested in the commit
  message (Ville)

Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Bob Paauwe <bob.j.paauwe@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dsi.h     |  3 +
 drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 99 +++++++++++++++++++-
 2 files changed, 100 insertions(+), 2 deletions(-)

Comments

Matt Roper Jan. 10, 2020, 6:39 p.m. UTC | #1
On Fri, Jan 10, 2020 at 10:11:23AM -0800, Vivek Kasireddy wrote:
> Parsing the i2c element is mainly done to transfer the payload from the
> MIPI sequence block to the relevant slave device. In some cases, the
> commands that are part of the payload can be used to turn on the backlight.
> 
> This patch is actually a refactored version of this old patch:
> https://lists.freedesktop.org/archives/intel-gfx/2014-December/056897.html
> 
> In addition to the refactoring, the original patch is augmented by looking up
> the i2c bus from ACPI NS instead of relying on the bus number provided
> in the VBT.
> 
> This patch was tested on Aava Mobile's Inari 10 tablet. It enabled
> turning on the backlight by transfering the payload to the device.
> 
> v2:
> - Add DRM_DEV_ERROR for invalid adapter and failed transfer and also
>   drop the DRM_DEBUG that existed originally. (Hans)
> - Add two gotos instead of one to clean things up properly.
> 
> v3:
> - Identify the device on which this patch was tested in the commit
>   message (Ville)
> 
> Cc: Hans de Goede <hdegoede@redhat.com>
> Cc: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Cc: Bob Paauwe <bob.j.paauwe@intel.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>

Since v3 is identical to v2 except for the commit message, I think we
can apply this based on v2's CI results.  The only CI failure was an
incomplete on a non-DSI TGL system and the incomplete happened long
after the VBT parsing changes here would have had any effect.

Applied to dinq.  Thanks for the patch and review.


Matt

> ---
>  drivers/gpu/drm/i915/display/intel_dsi.h     |  3 +
>  drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 99 +++++++++++++++++++-
>  2 files changed, 100 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi.h b/drivers/gpu/drm/i915/display/intel_dsi.h
> index 7481a5aa3084..6cef1356b4e6 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi.h
> +++ b/drivers/gpu/drm/i915/display/intel_dsi.h
> @@ -69,6 +69,9 @@ struct intel_dsi {
>  	/* number of DSI lanes */
>  	unsigned int lane_count;
>  
> +	/* i2c bus associated with the slave device */
> +	int i2c_bus_num;
> +
>  	/*
>  	 * video mode pixel format
>  	 *
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> index 0032161e0f76..89fb0d90b694 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> @@ -86,6 +86,12 @@ static struct gpio_map vlv_gpio_table[] = {
>  	{ VLV_GPIO_NC_11_PANEL1_BKLTCTL },
>  };
>  
> +struct i2c_adapter_lookup {
> +	u16 slave_addr;
> +	struct intel_dsi *intel_dsi;
> +	acpi_handle dev_handle;
> +};
> +
>  #define CHV_GPIO_IDX_START_N		0
>  #define CHV_GPIO_IDX_START_E		73
>  #define CHV_GPIO_IDX_START_SW		100
> @@ -378,11 +384,98 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
>  	return data;
>  }
>  
> +static int i2c_adapter_lookup(struct acpi_resource *ares, void *data)
> +{
> +	struct i2c_adapter_lookup *lookup = data;
> +	struct intel_dsi *intel_dsi = lookup->intel_dsi;
> +	struct acpi_resource_i2c_serialbus *sb;
> +	struct i2c_adapter *adapter;
> +	acpi_handle adapter_handle;
> +	acpi_status status;
> +
> +	if (intel_dsi->i2c_bus_num >= 0 ||
> +	    !i2c_acpi_get_i2c_resource(ares, &sb))
> +		return 1;
> +
> +	if (lookup->slave_addr != sb->slave_address)
> +		return 1;
> +
> +	status = acpi_get_handle(lookup->dev_handle,
> +				 sb->resource_source.string_ptr,
> +				 &adapter_handle);
> +	if (ACPI_FAILURE(status))
> +		return 1;
> +
> +	adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
> +	if (adapter)
> +		intel_dsi->i2c_bus_num = adapter->nr;
> +
> +	return 1;
> +}
> +
>  static const u8 *mipi_exec_i2c(struct intel_dsi *intel_dsi, const u8 *data)
>  {
> -	DRM_DEBUG_KMS("Skipping I2C element execution\n");
> +	struct drm_device *drm_dev = intel_dsi->base.base.dev;
> +	struct device *dev = &drm_dev->pdev->dev;
> +	struct i2c_adapter *adapter;
> +	struct acpi_device *acpi_dev;
> +	struct list_head resource_list;
> +	struct i2c_adapter_lookup lookup;
> +	struct i2c_msg msg;
> +	int ret;
> +	u8 vbt_i2c_bus_num = *(data + 2);
> +	u16 slave_addr = *(u16 *)(data + 3);
> +	u8 reg_offset = *(data + 5);
> +	u8 payload_size = *(data + 6);
> +	u8 *payload_data;
> +
> +	if (intel_dsi->i2c_bus_num < 0) {
> +		intel_dsi->i2c_bus_num = vbt_i2c_bus_num;
> +
> +		acpi_dev = ACPI_COMPANION(dev);
> +		if (acpi_dev) {
> +			memset(&lookup, 0, sizeof(lookup));
> +			lookup.slave_addr = slave_addr;
> +			lookup.intel_dsi = intel_dsi;
> +			lookup.dev_handle = acpi_device_handle(acpi_dev);
> +
> +			INIT_LIST_HEAD(&resource_list);
> +			acpi_dev_get_resources(acpi_dev, &resource_list,
> +					       i2c_adapter_lookup,
> +					       &lookup);
> +			acpi_dev_free_resource_list(&resource_list);
> +		}
> +	}
>  
> -	return data + *(data + 6) + 7;
> +	adapter = i2c_get_adapter(intel_dsi->i2c_bus_num);
> +	if (!adapter) {
> +		DRM_DEV_ERROR(dev, "Cannot find a valid i2c bus for xfer\n");
> +		goto err_bus;
> +	}
> +
> +	payload_data = kzalloc(payload_size + 1, GFP_KERNEL);
> +	if (!payload_data)
> +		goto err_alloc;
> +
> +	payload_data[0] = reg_offset;
> +	memcpy(&payload_data[1], (data + 7), payload_size);
> +
> +	msg.addr = slave_addr;
> +	msg.flags = 0;
> +	msg.len = payload_size + 1;
> +	msg.buf = payload_data;
> +
> +	ret = i2c_transfer(adapter, &msg, 1);
> +	if (ret < 0)
> +		DRM_DEV_ERROR(dev,
> +			      "Failed to xfer payload of size (%u) to reg (%u)\n",
> +			      payload_size, reg_offset);
> +
> +	kfree(payload_data);
> +err_alloc:
> +	i2c_put_adapter(adapter);
> +err_bus:
> +	return data + payload_size + 7;
>  }
>  
>  static const u8 *mipi_exec_spi(struct intel_dsi *intel_dsi, const u8 *data)
> @@ -683,6 +776,8 @@ bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
>  	intel_dsi->panel_off_delay = pps->panel_off_delay / 10;
>  	intel_dsi->panel_pwr_cycle_delay = pps->panel_power_cycle_delay / 10;
>  
> +	intel_dsi->i2c_bus_num = -1;
> +
>  	/* a regular driver would get the device in probe */
>  	for_each_dsi_port(port, intel_dsi->ports) {
>  		mipi_dsi_attach(intel_dsi->dsi_hosts[port]->device);
> -- 
> 2.21.1
>
Jani Nikula Jan. 13, 2020, 11:27 a.m. UTC | #2
On Fri, 10 Jan 2020, Vivek Kasireddy <vivek.kasireddy@intel.com> wrote:
> Parsing the i2c element is mainly done to transfer the payload from the
> MIPI sequence block to the relevant slave device. In some cases, the
> commands that are part of the payload can be used to turn on the backlight.
>
> This patch is actually a refactored version of this old patch:
> https://lists.freedesktop.org/archives/intel-gfx/2014-December/056897.html
>
> In addition to the refactoring, the original patch is augmented by looking up
> the i2c bus from ACPI NS instead of relying on the bus number provided
> in the VBT.

All this acpi business in the patch will fail the build on
CONFIG_ACPI=n.

BR,
Jani.

>
> This patch was tested on Aava Mobile's Inari 10 tablet. It enabled
> turning on the backlight by transfering the payload to the device.
>
> v2:
> - Add DRM_DEV_ERROR for invalid adapter and failed transfer and also
>   drop the DRM_DEBUG that existed originally. (Hans)
> - Add two gotos instead of one to clean things up properly.
>
> v3:
> - Identify the device on which this patch was tested in the commit
>   message (Ville)
>
> Cc: Hans de Goede <hdegoede@redhat.com>
> Cc: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
> Cc: Matt Roper <matthew.d.roper@intel.com>
> Cc: Bob Paauwe <bob.j.paauwe@intel.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dsi.h     |  3 +
>  drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 99 +++++++++++++++++++-
>  2 files changed, 100 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi.h b/drivers/gpu/drm/i915/display/intel_dsi.h
> index 7481a5aa3084..6cef1356b4e6 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi.h
> +++ b/drivers/gpu/drm/i915/display/intel_dsi.h
> @@ -69,6 +69,9 @@ struct intel_dsi {
>  	/* number of DSI lanes */
>  	unsigned int lane_count;
>  
> +	/* i2c bus associated with the slave device */
> +	int i2c_bus_num;
> +
>  	/*
>  	 * video mode pixel format
>  	 *
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> index 0032161e0f76..89fb0d90b694 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> @@ -86,6 +86,12 @@ static struct gpio_map vlv_gpio_table[] = {
>  	{ VLV_GPIO_NC_11_PANEL1_BKLTCTL },
>  };
>  
> +struct i2c_adapter_lookup {
> +	u16 slave_addr;
> +	struct intel_dsi *intel_dsi;
> +	acpi_handle dev_handle;
> +};
> +
>  #define CHV_GPIO_IDX_START_N		0
>  #define CHV_GPIO_IDX_START_E		73
>  #define CHV_GPIO_IDX_START_SW		100
> @@ -378,11 +384,98 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
>  	return data;
>  }
>  
> +static int i2c_adapter_lookup(struct acpi_resource *ares, void *data)
> +{
> +	struct i2c_adapter_lookup *lookup = data;
> +	struct intel_dsi *intel_dsi = lookup->intel_dsi;
> +	struct acpi_resource_i2c_serialbus *sb;
> +	struct i2c_adapter *adapter;
> +	acpi_handle adapter_handle;
> +	acpi_status status;
> +
> +	if (intel_dsi->i2c_bus_num >= 0 ||
> +	    !i2c_acpi_get_i2c_resource(ares, &sb))
> +		return 1;
> +
> +	if (lookup->slave_addr != sb->slave_address)
> +		return 1;
> +
> +	status = acpi_get_handle(lookup->dev_handle,
> +				 sb->resource_source.string_ptr,
> +				 &adapter_handle);
> +	if (ACPI_FAILURE(status))
> +		return 1;
> +
> +	adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
> +	if (adapter)
> +		intel_dsi->i2c_bus_num = adapter->nr;
> +
> +	return 1;
> +}
> +
>  static const u8 *mipi_exec_i2c(struct intel_dsi *intel_dsi, const u8 *data)
>  {
> -	DRM_DEBUG_KMS("Skipping I2C element execution\n");
> +	struct drm_device *drm_dev = intel_dsi->base.base.dev;
> +	struct device *dev = &drm_dev->pdev->dev;
> +	struct i2c_adapter *adapter;
> +	struct acpi_device *acpi_dev;
> +	struct list_head resource_list;
> +	struct i2c_adapter_lookup lookup;
> +	struct i2c_msg msg;
> +	int ret;
> +	u8 vbt_i2c_bus_num = *(data + 2);
> +	u16 slave_addr = *(u16 *)(data + 3);
> +	u8 reg_offset = *(data + 5);
> +	u8 payload_size = *(data + 6);
> +	u8 *payload_data;
> +
> +	if (intel_dsi->i2c_bus_num < 0) {
> +		intel_dsi->i2c_bus_num = vbt_i2c_bus_num;
> +
> +		acpi_dev = ACPI_COMPANION(dev);
> +		if (acpi_dev) {
> +			memset(&lookup, 0, sizeof(lookup));
> +			lookup.slave_addr = slave_addr;
> +			lookup.intel_dsi = intel_dsi;
> +			lookup.dev_handle = acpi_device_handle(acpi_dev);
> +
> +			INIT_LIST_HEAD(&resource_list);
> +			acpi_dev_get_resources(acpi_dev, &resource_list,
> +					       i2c_adapter_lookup,
> +					       &lookup);
> +			acpi_dev_free_resource_list(&resource_list);
> +		}
> +	}
>  
> -	return data + *(data + 6) + 7;
> +	adapter = i2c_get_adapter(intel_dsi->i2c_bus_num);
> +	if (!adapter) {
> +		DRM_DEV_ERROR(dev, "Cannot find a valid i2c bus for xfer\n");
> +		goto err_bus;
> +	}
> +
> +	payload_data = kzalloc(payload_size + 1, GFP_KERNEL);
> +	if (!payload_data)
> +		goto err_alloc;
> +
> +	payload_data[0] = reg_offset;
> +	memcpy(&payload_data[1], (data + 7), payload_size);
> +
> +	msg.addr = slave_addr;
> +	msg.flags = 0;
> +	msg.len = payload_size + 1;
> +	msg.buf = payload_data;
> +
> +	ret = i2c_transfer(adapter, &msg, 1);
> +	if (ret < 0)
> +		DRM_DEV_ERROR(dev,
> +			      "Failed to xfer payload of size (%u) to reg (%u)\n",
> +			      payload_size, reg_offset);
> +
> +	kfree(payload_data);
> +err_alloc:
> +	i2c_put_adapter(adapter);
> +err_bus:
> +	return data + payload_size + 7;
>  }
>  
>  static const u8 *mipi_exec_spi(struct intel_dsi *intel_dsi, const u8 *data)
> @@ -683,6 +776,8 @@ bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
>  	intel_dsi->panel_off_delay = pps->panel_off_delay / 10;
>  	intel_dsi->panel_pwr_cycle_delay = pps->panel_power_cycle_delay / 10;
>  
> +	intel_dsi->i2c_bus_num = -1;
> +
>  	/* a regular driver would get the device in probe */
>  	for_each_dsi_port(port, intel_dsi->ports) {
>  		mipi_dsi_attach(intel_dsi->dsi_hosts[port]->device);
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_dsi.h b/drivers/gpu/drm/i915/display/intel_dsi.h
index 7481a5aa3084..6cef1356b4e6 100644
--- a/drivers/gpu/drm/i915/display/intel_dsi.h
+++ b/drivers/gpu/drm/i915/display/intel_dsi.h
@@ -69,6 +69,9 @@  struct intel_dsi {
 	/* number of DSI lanes */
 	unsigned int lane_count;
 
+	/* i2c bus associated with the slave device */
+	int i2c_bus_num;
+
 	/*
 	 * video mode pixel format
 	 *
diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
index 0032161e0f76..89fb0d90b694 100644
--- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
+++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
@@ -86,6 +86,12 @@  static struct gpio_map vlv_gpio_table[] = {
 	{ VLV_GPIO_NC_11_PANEL1_BKLTCTL },
 };
 
+struct i2c_adapter_lookup {
+	u16 slave_addr;
+	struct intel_dsi *intel_dsi;
+	acpi_handle dev_handle;
+};
+
 #define CHV_GPIO_IDX_START_N		0
 #define CHV_GPIO_IDX_START_E		73
 #define CHV_GPIO_IDX_START_SW		100
@@ -378,11 +384,98 @@  static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
 	return data;
 }
 
+static int i2c_adapter_lookup(struct acpi_resource *ares, void *data)
+{
+	struct i2c_adapter_lookup *lookup = data;
+	struct intel_dsi *intel_dsi = lookup->intel_dsi;
+	struct acpi_resource_i2c_serialbus *sb;
+	struct i2c_adapter *adapter;
+	acpi_handle adapter_handle;
+	acpi_status status;
+
+	if (intel_dsi->i2c_bus_num >= 0 ||
+	    !i2c_acpi_get_i2c_resource(ares, &sb))
+		return 1;
+
+	if (lookup->slave_addr != sb->slave_address)
+		return 1;
+
+	status = acpi_get_handle(lookup->dev_handle,
+				 sb->resource_source.string_ptr,
+				 &adapter_handle);
+	if (ACPI_FAILURE(status))
+		return 1;
+
+	adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
+	if (adapter)
+		intel_dsi->i2c_bus_num = adapter->nr;
+
+	return 1;
+}
+
 static const u8 *mipi_exec_i2c(struct intel_dsi *intel_dsi, const u8 *data)
 {
-	DRM_DEBUG_KMS("Skipping I2C element execution\n");
+	struct drm_device *drm_dev = intel_dsi->base.base.dev;
+	struct device *dev = &drm_dev->pdev->dev;
+	struct i2c_adapter *adapter;
+	struct acpi_device *acpi_dev;
+	struct list_head resource_list;
+	struct i2c_adapter_lookup lookup;
+	struct i2c_msg msg;
+	int ret;
+	u8 vbt_i2c_bus_num = *(data + 2);
+	u16 slave_addr = *(u16 *)(data + 3);
+	u8 reg_offset = *(data + 5);
+	u8 payload_size = *(data + 6);
+	u8 *payload_data;
+
+	if (intel_dsi->i2c_bus_num < 0) {
+		intel_dsi->i2c_bus_num = vbt_i2c_bus_num;
+
+		acpi_dev = ACPI_COMPANION(dev);
+		if (acpi_dev) {
+			memset(&lookup, 0, sizeof(lookup));
+			lookup.slave_addr = slave_addr;
+			lookup.intel_dsi = intel_dsi;
+			lookup.dev_handle = acpi_device_handle(acpi_dev);
+
+			INIT_LIST_HEAD(&resource_list);
+			acpi_dev_get_resources(acpi_dev, &resource_list,
+					       i2c_adapter_lookup,
+					       &lookup);
+			acpi_dev_free_resource_list(&resource_list);
+		}
+	}
 
-	return data + *(data + 6) + 7;
+	adapter = i2c_get_adapter(intel_dsi->i2c_bus_num);
+	if (!adapter) {
+		DRM_DEV_ERROR(dev, "Cannot find a valid i2c bus for xfer\n");
+		goto err_bus;
+	}
+
+	payload_data = kzalloc(payload_size + 1, GFP_KERNEL);
+	if (!payload_data)
+		goto err_alloc;
+
+	payload_data[0] = reg_offset;
+	memcpy(&payload_data[1], (data + 7), payload_size);
+
+	msg.addr = slave_addr;
+	msg.flags = 0;
+	msg.len = payload_size + 1;
+	msg.buf = payload_data;
+
+	ret = i2c_transfer(adapter, &msg, 1);
+	if (ret < 0)
+		DRM_DEV_ERROR(dev,
+			      "Failed to xfer payload of size (%u) to reg (%u)\n",
+			      payload_size, reg_offset);
+
+	kfree(payload_data);
+err_alloc:
+	i2c_put_adapter(adapter);
+err_bus:
+	return data + payload_size + 7;
 }
 
 static const u8 *mipi_exec_spi(struct intel_dsi *intel_dsi, const u8 *data)
@@ -683,6 +776,8 @@  bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
 	intel_dsi->panel_off_delay = pps->panel_off_delay / 10;
 	intel_dsi->panel_pwr_cycle_delay = pps->panel_power_cycle_delay / 10;
 
+	intel_dsi->i2c_bus_num = -1;
+
 	/* a regular driver would get the device in probe */
 	for_each_dsi_port(port, intel_dsi->ports) {
 		mipi_dsi_attach(intel_dsi->dsi_hosts[port]->device);