diff mbox

[PATCHv4] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 driver

Message ID 20161112122911.19079-1-niklas.soderlund+renesas@ragnatech.se (mailing list archive)
State New, archived
Headers show

Commit Message

Niklas Söderlund Nov. 12, 2016, 12:29 p.m. UTC
A V4L2 driver for Renesas R-Car MIPI CSI-2 interface. The driver
supports the rcar-vin driver on R-Car Gen3 SoCs where a separate driver
is needed to receive CSI-2.

Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---

Changes since v3:
- Update DT binding documentation with input from Geert Uytterhoeven, 
  thanks!

Changes since v2:
- Added media control pads as this is needed by the new rcar-vin driver.
- Update DT bindings after review comments and to add r8a7796 support.
- Add get_fmt handler.
- Fix media bus format error s/YUYV8/UYVY8/

Changes since v1:
- Drop dependency on a pad aware s_stream operation.
- Use the DT bindings format "renesas,<soctype>-<device>", thanks Geert
  for pointing this out.

 .../devicetree/bindings/media/rcar-csi2.txt        | 116 ++++
 drivers/media/platform/rcar-vin/Kconfig            |  11 +
 drivers/media/platform/rcar-vin/Makefile           |   2 +
 drivers/media/platform/rcar-vin/rcar-csi2.c        | 586 +++++++++++++++++++++
 4 files changed, 715 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
 create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c

Comments

Geert Uytterhoeven Nov. 14, 2016, 8:29 a.m. UTC | #1
On Sat, Nov 12, 2016 at 1:29 PM, Niklas Söderlund
<niklas.soderlund+renesas@ragnatech.se> wrote:
> +Example:
> +
> +/* SoC properties */
> +
> +        csi20: csi2@fea80000 {
> +                compatible = "renesas,r8a7795-csi2";

7795

> +                reg = <0 0xfea80000 0 0x10000>;
> +                interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> +                clocks = <&cpg CPG_MOD 714>;
> +                power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;

7796

You'd better match the SoC part numbers ;-)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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Geert Uytterhoeven Nov. 15, 2016, 1:05 p.m. UTC | #2
On Sat, Nov 12, 2016 at 1:29 PM, Niklas Söderlund
<niklas.soderlund+renesas@ragnatech.se> wrote:
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt

> +The device node should contain two 'port' child nodes according to the
> +bindings defined in Documentation/devicetree/bindings/media/
> +video-interfaces.txt. Port 0 should connect the node that is the video
> +source for to the CSI-2. Port 1 should connect all the R-Car VIN

Trailing space at the end of previous line.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Laurent Pinchart Nov. 15, 2016, 7:04 p.m. UTC | #3
Hi Niklas,

Thank you for the patch.

On Saturday 12 Nov 2016 13:29:11 Niklas Söderlund wrote:
> A V4L2 driver for Renesas R-Car MIPI CSI-2 interface. The driver
> supports the rcar-vin driver on R-Car Gen3 SoCs where a separate driver
> is needed to receive CSI-2.
> 
> Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
> 
> Changes since v3:
> - Update DT binding documentation with input from Geert Uytterhoeven,
>   thanks!
> 
> Changes since v2:
> - Added media control pads as this is needed by the new rcar-vin driver.
> - Update DT bindings after review comments and to add r8a7796 support.
> - Add get_fmt handler.
> - Fix media bus format error s/YUYV8/UYVY8/
> 
> Changes since v1:
> - Drop dependency on a pad aware s_stream operation.
> - Use the DT bindings format "renesas,<soctype>-<device>", thanks Geert
>   for pointing this out.
> 
>  .../devicetree/bindings/media/rcar-csi2.txt        | 116 ++++
>  drivers/media/platform/rcar-vin/Kconfig            |  11 +
>  drivers/media/platform/rcar-vin/Makefile           |   2 +
>  drivers/media/platform/rcar-vin/rcar-csi2.c        | 586 ++++++++++++++++++
>  4 files changed, 715 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
>  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> 
> diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt
> b/Documentation/devicetree/bindings/media/rcar-csi2.txt new file mode
> 100644
> index 0000000..a9788e3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> @@ -0,0 +1,116 @@
> +Renesas R-Car MIPI CSI-2
> +------------------------
> +
> +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> +family of devices. It is to be used in conjunction with the R-Car VIN
> module, +which provides the video capture capabilities.
> +
> + - compatible: Must be one or more of the following
> +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> +
> +   When compatible with a generic version nodes must list the
> +   SoC-specific version corresponding to the platform first
> +   followed by the generic version.
> +
> + - reg: the register base and size for the device registers
> + - interrupts: the interrupt for the device
> + - clocks: Reference to the parent clock
> +
> +The device node should contain two 'port' child nodes according to the
> +bindings defined in Documentation/devicetree/bindings/media/
> +video-interfaces.txt. Port 0 should connect the node that is the video
> +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> +modules, which can make use of the CSI-2 module.
> +
> +- Port 0 - Video source
> +	- Reg 0 - sub-node describing the endpoint that is the video source
> +
> +- Port 1 - VIN instances
> +	- Reg 0 - sub-node describing the endpoint that is VIN0
> +	- Reg 1 - sub-node describing the endpoint that is VIN1
> +	- Reg 2 - sub-node describing the endpoint that is VIN2
> +	- Reg 3 - sub-node describing the endpoint that is VIN3
> +	- Reg 4 - sub-node describing the endpoint that is VIN4
> +	- Reg 5 - sub-node describing the endpoint that is VIN5
> +	- Reg 6 - sub-node describing the endpoint that is VIN6
> +	- Reg 7 - sub-node describing the endpoint that is VIN7
> +
> +Example:
> +
> +/* SoC properties */
> +
> +	 csi20: csi2@fea80000 {
> +		 compatible = "renesas,r8a7795-csi2";
> +		 reg = <0 0xfea80000 0 0x10000>;
> +		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> +		 clocks = <&cpg CPG_MOD 714>;
> +		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> +		 status = "disabled";
> +
> +		 ports {
> +			 #address-cells = <1>;
> +			 #size-cells = <0>;
> +
> +			 port@1 {
> +				 #address-cells = <1>;
> +				 #size-cells = <0>;
> +
> +				 reg = <1>;
> +
> +				 csi20vin0: endpoint@0 {
> +					 reg = <0>;
> +					 remote-endpoint = <&vin0csi20>;
> +				 };
> +				 csi20vin1: endpoint@1 {
> +					 reg = <1>;
> +					 remote-endpoint = <&vin1csi20>;
> +				 };
> +				 csi20vin2: endpoint@2 {
> +					 reg = <2>;
> +					 remote-endpoint = <&vin2csi20>;
> +				 };
> +				 csi20vin3: endpoint@3 {
> +					 reg = <3>;
> +					 remote-endpoint = <&vin3csi20>;
> +				 };
> +				 csi20vin4: endpoint@4 {
> +					 reg = <4>;
> +					 remote-endpoint = <&vin4csi20>;
> +				 };
> +				 csi20vin5: endpoint@5 {
> +					 reg = <5>;
> +					 remote-endpoint = <&vin5csi20>;
> +				 };
> +				 csi20vin6: endpoint@6 {
> +					 reg = <6>;
> +					 remote-endpoint = <&vin6csi20>;
> +				 };
> +				 csi20vin7: endpoint@7 {
> +					 reg = <7>;
> +					 remote-endpoint = <&vin7csi20>;
> +				 };
> +			 };
> +		 };
> +	 };
> +
> +/* Board properties */
> +
> +	&csi20 {
> +		status = "okay";
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;
> +				csi20_in: endpoint@0 {
> +					clock-lanes = <0>;
> +					data-lanes = <1>;
> +					remote-endpoint = <&adv7482_txb>;
> +				};
> +			};
> +		};
> +	};
> diff --git a/drivers/media/platform/rcar-vin/Kconfig
> b/drivers/media/platform/rcar-vin/Kconfig index 111d2a1..3606997 100644
> --- a/drivers/media/platform/rcar-vin/Kconfig
> +++ b/drivers/media/platform/rcar-vin/Kconfig
> @@ -9,3 +9,14 @@ config VIDEO_RCAR_VIN
> 
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called rcar-vin.
> +
> +config VIDEO_RCAR_CSI2
> +	tristate "R-Car MIPI CSI-2 Interface driver"

I would call this CSI-2 Receiver, as interface doesn't make it clear whether 
we're talking about a receiver or a transmitter. A (supervised) 
s/interface/receiver/ through the patch should do.

> +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> +	depends on ARCH_RENESAS || COMPILE_TEST
> +	---help---
> +	  Support for Renesas R-Car MIPI CSI-2 interface driver.
> +	  Supports R-Car Gen3 SoCs.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called rcar-csi2.
> diff --git a/drivers/media/platform/rcar-vin/Makefile
> b/drivers/media/platform/rcar-vin/Makefile index 48c5632..81a37f2 100644
> --- a/drivers/media/platform/rcar-vin/Makefile
> +++ b/drivers/media/platform/rcar-vin/Makefile
> @@ -1,3 +1,5 @@
>  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> 
>  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> +
> +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o

Nitpicking, I would keep these in alphabetical order (the same applies for 
Kconfig actually). There's also no need for a blank line between the two.

> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c
> b/drivers/media/platform/rcar-vin/rcar-csi2.c new file mode 100644
> index 0000000..13eb78b
> --- /dev/null
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -0,0 +1,586 @@
> +/*
> + * Driver for Renesas R-Car MIPI CSI-2

CSI-2 Receiver

> + *
> + * Copyright (C) 2016 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by
> the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <media/v4l2-of.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Register offsets */
> +#define TREF_REG		0x00 /* Control Timing Select */
> +#define SRST_REG		0x04 /* Software Reset */
> +#define PHYCNT_REG		0x08 /* PHY Operation Control */
> +#define CHKSUM_REG		0x0C /* Checksum Control */

Hex constants are usually lower case in the kernel.

> +#define VCDT_REG		0x10 /* Channel Data Type Select */
> +#define VCDT2_REG		0x14 /* Channel Data Type Select 2 */
> +#define FRDT_REG		0x18 /* Frame Data Type Select */
> +#define FLD_REG			0x1C /* Field Detection Control */
> +#define ASTBY_REG		0x20 /* Automatic Standby Control */
> +#define LNGDT0_REG		0x28 /* Long Data Type Setting 0 */
> +#define LNGDT1_REG		0x2C /* Long Data Type Setting 1 */
> +#define INTEN_REG		0x30 /* Interrupt Enable */
> +#define INTCLOSE_REG		0x34 /* Interrupt Source Mask */
> +#define INTSTATE_REG		0x38 /* Interrupt Status Monitor */
> +#define INTERRSTATE_REG		0x3C /* Interrupt Error Status Monitor 
*/
> +#define SHPDAT_REG		0x40 /* Short Packet Data */
> +#define SHPCNT_REG		0x44 /* Short Packet Count */
> +#define LINKCNT_REG		0x48 /* LINK Operation Control */
> +#define LSWAP_REG		0x4C /* Lane Swap */
> +#define PHTC_REG		0x58 /* PHY Test Interface Clear */
> +#define PHYPLL_REG		0x68 /* PHY Frequency Control */
> +#define PHEERM_REG		0x74 /* PHY ESC Error Monitor */
> +#define PHCLM_REG		0x78 /* PHY Clock Lane Monitor */
> +#define PHDLM_REG		0x7C /* PHY Data Lane Monitor */

I would have prefixed the register names (and bits below) with CSI2_ or 
RCAR_CSI2_ to avoid name space clashes, but that's up to you.

> +/* Control Timing Select bits */
> +#define TREF_TREF			(1 << 0)

Another matter of personal taste, I like having bits definitions right after 
the register they're related to, it improves readability in my opinion (and 
you won't need the comments before the bits).

> +
> +/* Software Reset bits */
> +#define SRST_SRST			(1 << 0)
> +
> +/* PHY Operation Control bits */
> +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> +#define PHYCNT_RSTZ			(1 << 16)
> +#define PHYCNT_ENABLECLK		(1 << 4)
> +#define PHYCNT_ENABLE_3			(1 << 3)
> +#define PHYCNT_ENABLE_2			(1 << 2)
> +#define PHYCNT_ENABLE_1			(1 << 1)
> +#define PHYCNT_ENABLE_0			(1 << 0)
> +
> +/* Checksum Control bits */
> +#define CHKSUM_ECC_EN			(1 << 1)
> +#define CHKSUM_CRC_EN			(1 << 0)
> +
> +/*
> + * Channel Data Type Select bits
> + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> + */
> +#define VCDT_VCDTN_EN			(1 << 15)
> +#define VCDT_SEL_VC(n)			((n & 0x3) << 8)

You should use (n) in case n is an expression, otherwise subtle macro side 
effects can occur, which can be difficult to debug.

> +#define VCDT_SEL_DTN_ON			(1 << 6)
> +#define VCDT_SEL_DT(n)			((n & 0x1f) << 0)
> +
> +/* Field Detection Control bits */
> +#define FLD_FLD_NUM(n)			((n & 0xff) << 16)
> +#define FLD_FLD_EN4			(1 << 3)
> +#define FLD_FLD_EN3			(1 << 2)
> +#define FLD_FLD_EN2			(1 << 1)
> +#define FLD_FLD_EN			(1 << 0)
> +
> +/* LINK Operation Control bits */
> +#define LINKCNT_MONITOR_EN		(1 << 31)
> +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> +
> +/* Lane Swap bits */
> +#define LSWAP_L3SEL(n)			((n & 0x3) << 6)
> +#define LSWAP_L2SEL(n)			((n & 0x3) << 4)
> +#define LSWAP_L1SEL(n)			((n & 0x3) << 2)
> +#define LSWAP_L0SEL(n)			((n & 0x3) << 0)
> +
> +/* PHY Test Interface Clear bits */
> +#define PHTC_TESTCLR			(1 << 0)
> +
> +/* PHY Frequency Control bits */

I wonder who came up with those strange frequencies to register values 
mappings...

> +#define PHYPLL_HSFREQRANGE_80MBPS	(0x00 << 16)
> +#define PHYPLL_HSFREQRANGE_90MBPS	(0x10 << 16)
> +#define PHYPLL_HSFREQRANGE_100MBPS	(0x20 << 16)
> +#define PHYPLL_HSFREQRANGE_110MBPS	(0x30 << 16)
> +#define PHYPLL_HSFREQRANGE_120MBPS	(0x01 << 16)
> +#define PHYPLL_HSFREQRANGE_130MBPS	(0x11 << 16)
> +#define PHYPLL_HSFREQRANGE_140MBPS	(0x21 << 16)
> +#define PHYPLL_HSFREQRANGE_150MBPS	(0x31 << 16)
> +#define PHYPLL_HSFREQRANGE_160MBPS	(0x02 << 16)
> +#define PHYPLL_HSFREQRANGE_170MBPS	(0x12 << 16)
> +#define PHYPLL_HSFREQRANGE_180MBPS	(0x22 << 16)
> +#define PHYPLL_HSFREQRANGE_190MBPS	(0x32 << 16)
> +#define PHYPLL_HSFREQRANGE_205MBPS	(0x03 << 16)
> +#define PHYPLL_HSFREQRANGE_220MBPS	(0x13 << 16)
> +#define PHYPLL_HSFREQRANGE_235MBPS	(0x23 << 16)
> +#define PHYPLL_HSFREQRANGE_250MBPS	(0x33 << 16)
> +#define PHYPLL_HSFREQRANGE_275MBPS	(0x04 << 16)
> +#define PHYPLL_HSFREQRANGE_300MBPS	(0x14 << 16)
> +#define PHYPLL_HSFREQRANGE_325MBPS	(0x05 << 16)
> +#define PHYPLL_HSFREQRANGE_350MBPS	(0x15 << 16)
> +#define PHYPLL_HSFREQRANGE_400MBPS	(0x25 << 16)
> +#define PHYPLL_HSFREQRANGE_450MBPS	(0x06 << 16)
> +#define PHYPLL_HSFREQRANGE_500MBPS	(0x16 << 16)
> +#define PHYPLL_HSFREQRANGE_550MBPS	(0x07 << 16)
> +#define PHYPLL_HSFREQRANGE_600MBPS	(0x17 << 16)
> +#define PHYPLL_HSFREQRANGE_650MBPS	(0x08 << 16)
> +#define PHYPLL_HSFREQRANGE_700MBPS	(0x18 << 16)
> +#define PHYPLL_HSFREQRANGE_750MBPS	(0x09 << 16)
> +#define PHYPLL_HSFREQRANGE_800MBPS	(0x19 << 16)
> +#define PHYPLL_HSFREQRANGE_850MBPS	(0x29 << 16)
> +#define PHYPLL_HSFREQRANGE_900MBPS	(0x39 << 16)
> +#define PHYPLL_HSFREQRANGE_950MBPS	(0x0A << 16)
> +#define PHYPLL_HSFREQRANGE_1000MBPS	(0x1A << 16)
> +#define PHYPLL_HSFREQRANGE_1050MBPS	(0x2A << 16)
> +#define PHYPLL_HSFREQRANGE_1100MBPS	(0x3A << 16)
> +#define PHYPLL_HSFREQRANGE_1150MBPS	(0x0B << 16)
> +#define PHYPLL_HSFREQRANGE_1200MBPS	(0x1B << 16)
> +#define PHYPLL_HSFREQRANGE_1250MBPS	(0x2B << 16)
> +#define PHYPLL_HSFREQRANGE_1300MBPS	(0x3B << 16)
> +#define PHYPLL_HSFREQRANGE_1350MBPS	(0x0C << 16)
> +#define PHYPLL_HSFREQRANGE_1400MBPS	(0x1C << 16)
> +#define PHYPLL_HSFREQRANGE_1450MBPS	(0x2C << 16)
> +#define PHYPLL_HSFREQRANGE_1500MBPS	(0x3C << 16)
> +
> +enum rcar_csi2_pads {
> +	RCAR_CSI2_SINK,
> +	RCAR_CSI2_SOURCE_VC0,
> +	RCAR_CSI2_SOURCE_VC1,
> +	RCAR_CSI2_SOURCE_VC2,
> +	RCAR_CSI2_SOURCE_VC3,
> +	RCAR_CSI2_PAD_MAX,
> +};
> +
> +struct rcar_csi2 {
> +	struct device *dev;
> +	void __iomem *base;
> +	spinlock_t lock;

All locks should have a comment describing what they protect.

> +
> +	unsigned short lanes;
> +	unsigned char swap[4];

Maybe lane_swap ?

> +
> +	struct v4l2_subdev subdev;
> +	struct media_pad pads[RCAR_CSI2_PAD_MAX];
> +	struct v4l2_mbus_framefmt mf;
> +};
> +
> +#define csi_dbg(p, fmt, arg...)		dev_dbg(p->dev, fmt, ##arg)
> +#define csi_info(p, fmt, arg...)	dev_info(p->dev, fmt, ##arg)
> +#define csi_warn(p, fmt, arg...)	dev_warn(p->dev, fmt, ##arg)
> +#define csi_err(p, fmt, arg...)		dev_err(p->dev, fmt, ##arg)

I wonder if these macros are really worth it, they only shorten lines by 4 
characters, but hide the fact that we use dev_*.

> +static irqreturn_t rcar_csi2_irq(int irq, void *data)
> +{
> +	struct rcar_csi2 *priv = data;
> +	u32 int_status;
> +	unsigned int handled = 0;
> +
> +	spin_lock(&priv->lock);
> +
> +	int_status = ioread32(priv->base + INTSTATE_REG);

I'd create two functions to access registers:

static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
{
	return ioread32(priv->base + reg);
}

static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 
data)
{
	iowrite32(data, priv->base + reg);
}

It would in my opinion improve readability and make it easy to log read and 
writes for debug purpose should the need arise.

> +	if (!int_status)
> +		goto done;
> +
> +	/* ack interrupts */
> +	iowrite32(int_status, priv->base + INTSTATE_REG);
> +	handled = 1;

If you don't need to handle interrupts, how about not enabling them in the 
first place ? :-) Keep it in the DT bindings though, and check in the probe 
function that it has been specified, in order to ensure that we'll be able to 
use it later if needed.

> +done:
> +	spin_unlock(&priv->lock);
> +
> +	return IRQ_RETVAL(handled);
> +
> +}
> +
> +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> +{
> +	iowrite32(SRST_SRST, priv->base + SRST_REG);
> +	udelay(5);

Is the delay really needed ? I see no mention of it in section 25.3.12 of the 
datasheet.

> +	iowrite32(0, priv->base + SRST_REG);
> +}
> +
> +static void rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> +{
> +	int timeout;
> +
> +	/* Read the PHY clock lane monitor register (PHCLM). */
> +	for (timeout = 100; timeout >= 0; timeout--) {
> +		if (ioread32(priv->base + PHCLM_REG) & 0x01) {
> +			csi_dbg(priv, "Detected the PHY clock lane\n");
> +			break;
> +		}
> +		msleep(20);
> +	}
> +	if (!timeout)
> +		csi_err(priv, "Timeout of reading the PHY clock lane\n");

Shouldn't this be a fatal error ?

> +
> +

Extra blank line.

> +	/* Read the PHY data lane monitor register (PHDLM). */
> +	for (timeout = 100; timeout >= 0; timeout--) {
> +		if (ioread32(priv->base + PHDLM_REG) & 0x01) {

Shouldn't you take all used data lanes into account, not just lane 0 ?

> +			csi_dbg(priv, "Detected the PHY data lane\n");
> +			break;
> +		}
> +		msleep(20);
> +	}
> +	if (!timeout)
> +		csi_err(priv, "Timeout of reading the PHY data lane\n");

And this too ?

> +

Extra blank line.

So this code waits for all data and clock lanes to enter LP-11 state. I'd 
update the comments to make that clear. I would also possibly combine the two 
loops, as there's no real need to wait for the clock and data lanes 
separately. Maybe something like

	/* Wait for the clock and data lanes to enter LP-11 state. */
	for (timeout = 100; timeout >= 0; timeout--) {
		const u32 lane_mask = (1 << priv->lanes) - 1;

		if ((rcar_csi2_read(priv, PHDLM_REG) & 1) == 1 &&
		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == 
lane_mask)
			return 0;

		msleep(20);
	}

	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
	return -ETIMEDOUT;

Although if you prefer keeping them separate that's fine too, but the comment 
and error messages should be updated (you could also print which data lane(s) 
didn't switch to LP-11, that could be useful for debugging).

> +}
> +
> +static int rcar_csi2_start(struct rcar_csi2 *priv)
> +{
> +	u32 fld, phycnt, phypll, vcdt, vcdt2, tmp, pixels;
> +	int i;

unsigned int.

> +
> +	csi_dbg(priv, "Input size (%dx%d%c)\n", priv->mf.width, priv-
>mf.height,
> +		priv->mf.field == V4L2_FIELD_NONE ? 'p' : 'i');
> +
> +	vcdt = vcdt2 = 0;

You can initialize the variables when declaring them.

> +	for (i = 0; i < priv->lanes; i++) {
> +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON;
> +
> +		switch (priv->mf.code) {
> +		case MEDIA_BUS_FMT_RGB888_1X24:
> +			/* 24 == RGB888 */
> +			tmp |= 0x24;
> +			break;
> +		case MEDIA_BUS_FMT_UYVY8_1X16:
> +		case MEDIA_BUS_FMT_UYVY8_2X8:
> +		case MEDIA_BUS_FMT_YUYV10_2X10:
> +			/* 1E == YUV422 8-bit */
> +			tmp |= 0x1e;
> +			break;
> +		default:
> +			csi_warn(priv,
> +				 "Unknown media bus format, try it anyway\n");
> +			break;
> +		}
> +
> +		/* Store in correct reg and offset */
> +		if (i < 2)
> +			vcdt |= tmp << ((i % 2) * 16);
> +		else
> +			vcdt2 |= tmp << ((i % 2) * 16);

These settings are per channel (which I expect map to source pads), not per 
lane.

> +	}
> +
> +	switch (priv->lanes) {
> +	case 1:
> +		fld = FLD_FLD_NUM(1) | FLD_FLD_EN;

This has nothing to do with lanes either :-)

> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> +		phypll = PHYPLL_HSFREQRANGE_400MBPS;
> +		break;
> +	case 4:
> +		fld = FLD_FLD_NUM(2) | FLD_FLD_EN4 | FLD_FLD_EN3 |
> +			FLD_FLD_EN2 | FLD_FLD_EN;
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 |
> +			PHYCNT_ENABLE_2 | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +
> +		/* Calculate MBPS per lane, assume 32 bits per pixel at 60Hz 
*/
> +		pixels = (priv->mf.width * priv->mf.height) /
> +			(priv->mf.field == V4L2_FIELD_NONE ? 1 : 2);
> +		if (pixels <= 640 * 480)
> +			phypll = PHYPLL_HSFREQRANGE_100MBPS;
> +		else if (pixels <= 720 * 576)
> +			phypll = PHYPLL_HSFREQRANGE_190MBPS;
> +		else if (pixels <= 1280 * 720)
> +			phypll = PHYPLL_HSFREQRANGE_450MBPS;
> +		else if (pixels <= 1920 * 1080)
> +			phypll = PHYPLL_HSFREQRANGE_900MBPS;
> +		else
> +			goto error;

That's a pretty bad heuristics as the bit rate doesn't depend on the image 
size only. You should instead query the information from the connected subdev 
using the V4L2_CID_LINK_FREQ control (you will obviously have to implement the 
control in the ADV7482 driver). See isp_video_check_external_subdevs() for an 
example of how this is done with the V4L2_CID_PIXEL_RATE control. Note that 
CSI-2 is a DDR bus, so the data rate per lane is twice the frequency.

You might want to tabulate the PLL register value for the input frequency 
ranges instead of using a bit if ... else ..., especially given that the 
datasheet contains a table much larger than the above 4 values.

> +
> +		break;
> +	default:
> +		goto error;
> +	}
> +
> +	/* Init */
> +	iowrite32(TREF_TREF, priv->base + TREF_REG);
> +	rcar_csi2_reset(priv);
> +	iowrite32(0, priv->base + PHTC_REG);
> +
> +	/* Configure */
> +	iowrite32(fld, priv->base + FLD_REG);
> +	iowrite32(vcdt, priv->base + VCDT_REG);
> +	iowrite32(vcdt2, priv->base + VCDT2_REG);
> +	iowrite32(LSWAP_L0SEL(priv->swap[0]) | LSWAP_L1SEL(priv->swap[1]) |
> +		  LSWAP_L2SEL(priv->swap[2]) | LSWAP_L3SEL(priv->swap[3]),
> +		  priv->base + LSWAP_REG);
> +
> +	/* Start */
> +	iowrite32(phypll, priv->base + PHYPLL_REG);
> +	iowrite32(phycnt, priv->base + PHYCNT_REG);
> +	iowrite32(LINKCNT_MONITOR_EN | LINKCNT_REG_MONI_PACT_EN |
> +		  LINKCNT_ICLK_NONSTOP, priv->base + LINKCNT_REG);
> +	iowrite32(phycnt | PHYCNT_SHUTDOWNZ, priv->base + PHYCNT_REG);
> +	iowrite32(phycnt | PHYCNT_SHUTDOWNZ | PHYCNT_RSTZ,
> +		  priv->base + PHYCNT_REG);
> +
> +	rcar_csi2_wait_phy_start(priv);
> +
> +	return 0;
> +error:
> +	csi_err(priv, "Unsupported resolution (%dx%d%c)\n",
> +		priv->mf.width, priv->mf.height,
> +		priv->mf.field == V4L2_FIELD_NONE ? 'p' : 'i');
> +
> +	return -EINVAL;
> +}
> +
> +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> +{
> +	iowrite32(0, priv->base + PHYCNT_REG);
> +
> +	rcar_csi2_reset(priv);
> +}
> +
> +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);

It's quite customary to create an inline function to do the conversion:

static inline struct rcar_csi2 *to_csi2(struct v4l2_subdev *sd)
{
	return container_of(sd, struct rcar_csi2, subdev);
}

and place it right after the structure definition.

> +
> +	if (enable)
> +		return rcar_csi2_start(priv);
> +
> +	rcar_csi2_stop(priv);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (format->pad != RCAR_CSI2_SINK)
> +		return -EINVAL;

Why is that ? The format on the sink pad should be configurable.

> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> +		priv->mf = format->format;

How about the V4L2_SUBDEV_FORMAT_ACTIVE formats ? You also need to validate 
the format here.

> +	return 0;
> +}
> +
> +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (format->pad != RCAR_CSI2_SINK)
> +		return -EINVAL;
> +
> +	format->format = priv->mf;

Similar comments here as for the set format implementation.

> +	return 0;
> +}
> +
> +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (on)
> +		pm_runtime_get_sync(priv->dev);
> +	else
> +		pm_runtime_put_sync(priv->dev);

You can probably use pm_runtime_put().

> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> +	.s_stream = rcar_csi2_s_stream,
> +};
> +
> +static struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> +	.s_power = rcar_csi2_s_power,
> +};
> +
> +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> +	.set_fmt = rcar_csi2_set_pad_format,
> +	.get_fmt = rcar_csi2_get_pad_format,
> +};
> +
> +static struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> +	.video	= &rcar_csi2_video_ops,
> +	.core	= &rcar_csi2_subdev_core_ops,
> +	.pad	= &rcar_csi2_pad_ops,
> +};
> +
> +/* ------------------------------------------------------------------------
> + * Platform Device Driver
> + */
> +
> +static const struct of_device_id rcar_csi2_of_table[] = {
> +	{ .compatible = "renesas,r8a7795-csi2" },
> +	{ .compatible = "renesas,r8a7796-csi2" },

You don't need to list those two compatible strings explicitly, the generic 
one will be enough.

> +	{ .compatible = "renesas,rcar-gen3-csi2" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> +
> +static int rcar_csi2_parse_dt(struct rcar_csi2 *priv)
> +{
> +	struct v4l2_of_endpoint v4l2_ep;
> +	struct device_node *ep;
> +	int i, n, ret;

i can be an unsigned int.

> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep)
> +		return -EINVAL;
> +
> +	ret = v4l2_of_parse_endpoint(ep, &v4l2_ep);
> +	of_node_put(ep);
> +	if (ret) {
> +		csi_err(priv, "Could not parse v4l2 endpoint\n");
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		csi_err(priv, "Unsupported media bus type for %s\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	switch (v4l2_ep.bus.mipi_csi2.num_data_lanes) {
> +	case 1:
> +	case 4:
> +		priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> +		break;
> +	default:
> +		csi_err(priv, "Unsupported number of lanes\n");

Shouldn't we also support the 2 lanes case ?

> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < 4; i++)
> +		priv->swap[i] = i;

Is this needed given that your overwrite swap right below ?
> +
> +	for (i = 0; i < priv->lanes; i++) {
> +		/* Check for valid lane number */
> +		if (v4l2_ep.bus.mipi_csi2.data_lanes[i] < 1 ||
> +		    v4l2_ep.bus.mipi_csi2.data_lanes[i] > 4) {
> +			csi_err(priv, "data lanes must be in 1-4 range\n");
> +			return -EINVAL;
> +		}
> +
> +		/* Use lane numbers 0-3 internally */
> +		priv->swap[i] = v4l2_ep.bus.mipi_csi2.data_lanes[i] - 1;
> +
> +

Extra blank lines.

> +	}
> +
> +	/* Make sure there are no duplicates */
> +	for (i = 0; i < priv->lanes; i++) {
> +		for (n = i + 1; n < priv->lanes; n++) {
> +			if (priv->swap[i] == priv->swap[n]) {
> +				csi_err(priv,
> +					"Requested swapping not possible\n");
> +				return -EINVAL;
> +			}
> +		}
> +	}

I believe it would make sense to move this code to v4l2_of_parse_endpoint().

> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> +				     struct platform_device *pdev)
> +{
> +	struct resource *mem;
> +	int irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!mem)
> +		return -ENODEV;
> +
> +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (!irq)
> +		return -ENODEV;
> +
> +	return devm_request_irq(&pdev->dev, irq, rcar_csi2_irq, IRQF_SHARED,
> +				dev_name(&pdev->dev), priv);
> +}
> +
> +static int rcar_csi2_probe(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv;
> +	unsigned int i;
> +	int ret;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(struct rcar_csi2), GFP_KERNEL);

sizeof(*priv)

> +	if (!priv)
> +		return -ENOMEM;
> +
> +

Extra blank line.

> +	priv->dev = &pdev->dev;
> +	spin_lock_init(&priv->lock);
> +
> +	ret = rcar_csi2_parse_dt(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_probe_resources(priv, pdev);
> +	if (ret) {
> +		csi_err(priv, "Failed to get resources\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, priv);
> +
> +	priv->subdev.owner = THIS_MODULE;
> +	priv->subdev.dev = &pdev->dev;
> +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.%s",
> +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> +
> +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	priv->subdev.entity.flags |= MEDIA_ENT_F_ATV_DECODER;

You probably need a new function, this isn't an analog TV decoder. Beside 
that, the field you want to initialize is priv->subdev.entity.function.

> +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> +	for (i = RCAR_CSI2_SOURCE_VC0; i < RCAR_CSI2_PAD_MAX; i++)
> +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&priv->subdev.entity, RCAR_CSI2_PAD_MAX,
> +				     priv->pads);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_async_register_subdev(&priv->subdev);
> +	if (ret < 0)
> +		return ret;
> +
> +	pm_runtime_enable(&pdev->dev);
> +
> +	csi_info(priv, "%d lanes found\n", priv->lanes);
> +
> +	return 0;
> +}
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
new file mode 100644
index 0000000..a9788e3
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
@@ -0,0 +1,116 @@ 
+Renesas R-Car MIPI CSI-2
+------------------------
+
+The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
+family of devices. It is to be used in conjunction with the R-Car VIN module,
+which provides the video capture capabilities.
+
+ - compatible: Must be one or more of the following
+   - "renesas,r8a7795-csi2" for the R8A7795 device.
+   - "renesas,r8a7796-csi2" for the R8A7796 device.
+   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
+
+   When compatible with a generic version nodes must list the
+   SoC-specific version corresponding to the platform first
+   followed by the generic version.
+
+ - reg: the register base and size for the device registers
+ - interrupts: the interrupt for the device
+ - clocks: Reference to the parent clock
+
+The device node should contain two 'port' child nodes according to the
+bindings defined in Documentation/devicetree/bindings/media/
+video-interfaces.txt. Port 0 should connect the node that is the video
+source for to the CSI-2. Port 1 should connect all the R-Car VIN 
+modules, which can make use of the CSI-2 module.
+
+- Port 0 - Video source
+	- Reg 0 - sub-node describing the endpoint that is the video source
+
+- Port 1 - VIN instances
+	- Reg 0 - sub-node describing the endpoint that is VIN0
+	- Reg 1 - sub-node describing the endpoint that is VIN1
+	- Reg 2 - sub-node describing the endpoint that is VIN2
+	- Reg 3 - sub-node describing the endpoint that is VIN3
+	- Reg 4 - sub-node describing the endpoint that is VIN4
+	- Reg 5 - sub-node describing the endpoint that is VIN5
+	- Reg 6 - sub-node describing the endpoint that is VIN6
+	- Reg 7 - sub-node describing the endpoint that is VIN7
+
+Example:
+
+/* SoC properties */
+
+	 csi20: csi2@fea80000 {
+		 compatible = "renesas,r8a7795-csi2";
+		 reg = <0 0xfea80000 0 0x10000>;
+		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
+		 clocks = <&cpg CPG_MOD 714>;
+		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
+		 status = "disabled";
+
+		 ports {
+			 #address-cells = <1>;
+			 #size-cells = <0>;
+
+			 port@1 {
+				 #address-cells = <1>;
+				 #size-cells = <0>;
+
+				 reg = <1>;
+
+				 csi20vin0: endpoint@0 {
+					 reg = <0>;
+					 remote-endpoint = <&vin0csi20>;
+				 };
+				 csi20vin1: endpoint@1 {
+					 reg = <1>;
+					 remote-endpoint = <&vin1csi20>;
+				 };
+				 csi20vin2: endpoint@2 {
+					 reg = <2>;
+					 remote-endpoint = <&vin2csi20>;
+				 };
+				 csi20vin3: endpoint@3 {
+					 reg = <3>;
+					 remote-endpoint = <&vin3csi20>;
+				 };
+				 csi20vin4: endpoint@4 {
+					 reg = <4>;
+					 remote-endpoint = <&vin4csi20>;
+				 };
+				 csi20vin5: endpoint@5 {
+					 reg = <5>;
+					 remote-endpoint = <&vin5csi20>;
+				 };
+				 csi20vin6: endpoint@6 {
+					 reg = <6>;
+					 remote-endpoint = <&vin6csi20>;
+				 };
+				 csi20vin7: endpoint@7 {
+					 reg = <7>;
+					 remote-endpoint = <&vin7csi20>;
+				 };
+			 };
+		 };
+	 };
+
+/* Board properties */
+
+	&csi20 {
+		status = "okay";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				csi20_in: endpoint@0 {
+					clock-lanes = <0>;
+					data-lanes = <1>;
+					remote-endpoint = <&adv7482_txb>;
+				};
+			};
+		};
+	};
diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
index 111d2a1..3606997 100644
--- a/drivers/media/platform/rcar-vin/Kconfig
+++ b/drivers/media/platform/rcar-vin/Kconfig
@@ -9,3 +9,14 @@  config VIDEO_RCAR_VIN
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called rcar-vin.
+
+config VIDEO_RCAR_CSI2
+	tristate "R-Car MIPI CSI-2 Interface driver"
+	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
+	depends on ARCH_RENESAS || COMPILE_TEST
+	---help---
+	  Support for Renesas R-Car MIPI CSI-2 interface driver.
+	  Supports R-Car Gen3 SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rcar-csi2.
diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
index 48c5632..81a37f2 100644
--- a/drivers/media/platform/rcar-vin/Makefile
+++ b/drivers/media/platform/rcar-vin/Makefile
@@ -1,3 +1,5 @@ 
 rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
 
 obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
+
+obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
new file mode 100644
index 0000000..13eb78b
--- /dev/null
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -0,0 +1,586 @@ 
+/*
+ * Driver for Renesas R-Car MIPI CSI-2
+ *
+ * Copyright (C) 2016 Renesas Electronics Corp.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <media/v4l2-of.h>
+#include <media/v4l2-subdev.h>
+
+/* Register offsets */
+#define TREF_REG		0x00 /* Control Timing Select */
+#define SRST_REG		0x04 /* Software Reset */
+#define PHYCNT_REG		0x08 /* PHY Operation Control */
+#define CHKSUM_REG		0x0C /* Checksum Control */
+#define VCDT_REG		0x10 /* Channel Data Type Select */
+#define VCDT2_REG		0x14 /* Channel Data Type Select 2 */
+#define FRDT_REG		0x18 /* Frame Data Type Select */
+#define FLD_REG			0x1C /* Field Detection Control */
+#define ASTBY_REG		0x20 /* Automatic Standby Control */
+#define LNGDT0_REG		0x28 /* Long Data Type Setting 0 */
+#define LNGDT1_REG		0x2C /* Long Data Type Setting 1 */
+#define INTEN_REG		0x30 /* Interrupt Enable */
+#define INTCLOSE_REG		0x34 /* Interrupt Source Mask */
+#define INTSTATE_REG		0x38 /* Interrupt Status Monitor */
+#define INTERRSTATE_REG		0x3C /* Interrupt Error Status Monitor */
+#define SHPDAT_REG		0x40 /* Short Packet Data */
+#define SHPCNT_REG		0x44 /* Short Packet Count */
+#define LINKCNT_REG		0x48 /* LINK Operation Control */
+#define LSWAP_REG		0x4C /* Lane Swap */
+#define PHTC_REG		0x58 /* PHY Test Interface Clear */
+#define PHYPLL_REG		0x68 /* PHY Frequency Control */
+#define PHEERM_REG		0x74 /* PHY ESC Error Monitor */
+#define PHCLM_REG		0x78 /* PHY Clock Lane Monitor */
+#define PHDLM_REG		0x7C /* PHY Data Lane Monitor */
+
+/* Control Timing Select bits */
+#define TREF_TREF			(1 << 0)
+
+/* Software Reset bits */
+#define SRST_SRST			(1 << 0)
+
+/* PHY Operation Control bits */
+#define PHYCNT_SHUTDOWNZ		(1 << 17)
+#define PHYCNT_RSTZ			(1 << 16)
+#define PHYCNT_ENABLECLK		(1 << 4)
+#define PHYCNT_ENABLE_3			(1 << 3)
+#define PHYCNT_ENABLE_2			(1 << 2)
+#define PHYCNT_ENABLE_1			(1 << 1)
+#define PHYCNT_ENABLE_0			(1 << 0)
+
+/* Checksum Control bits */
+#define CHKSUM_ECC_EN			(1 << 1)
+#define CHKSUM_CRC_EN			(1 << 0)
+
+/*
+ * Channel Data Type Select bits
+ * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
+ * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
+ */
+#define VCDT_VCDTN_EN			(1 << 15)
+#define VCDT_SEL_VC(n)			((n & 0x3) << 8)
+#define VCDT_SEL_DTN_ON			(1 << 6)
+#define VCDT_SEL_DT(n)			((n & 0x1f) << 0)
+
+/* Field Detection Control bits */
+#define FLD_FLD_NUM(n)			((n & 0xff) << 16)
+#define FLD_FLD_EN4			(1 << 3)
+#define FLD_FLD_EN3			(1 << 2)
+#define FLD_FLD_EN2			(1 << 1)
+#define FLD_FLD_EN			(1 << 0)
+
+/* LINK Operation Control bits */
+#define LINKCNT_MONITOR_EN		(1 << 31)
+#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
+#define LINKCNT_ICLK_NONSTOP		(1 << 24)
+
+/* Lane Swap bits */
+#define LSWAP_L3SEL(n)			((n & 0x3) << 6)
+#define LSWAP_L2SEL(n)			((n & 0x3) << 4)
+#define LSWAP_L1SEL(n)			((n & 0x3) << 2)
+#define LSWAP_L0SEL(n)			((n & 0x3) << 0)
+
+/* PHY Test Interface Clear bits */
+#define PHTC_TESTCLR			(1 << 0)
+
+/* PHY Frequency Control bits */
+#define PHYPLL_HSFREQRANGE_80MBPS	(0x00 << 16)
+#define PHYPLL_HSFREQRANGE_90MBPS	(0x10 << 16)
+#define PHYPLL_HSFREQRANGE_100MBPS	(0x20 << 16)
+#define PHYPLL_HSFREQRANGE_110MBPS	(0x30 << 16)
+#define PHYPLL_HSFREQRANGE_120MBPS	(0x01 << 16)
+#define PHYPLL_HSFREQRANGE_130MBPS	(0x11 << 16)
+#define PHYPLL_HSFREQRANGE_140MBPS	(0x21 << 16)
+#define PHYPLL_HSFREQRANGE_150MBPS	(0x31 << 16)
+#define PHYPLL_HSFREQRANGE_160MBPS	(0x02 << 16)
+#define PHYPLL_HSFREQRANGE_170MBPS	(0x12 << 16)
+#define PHYPLL_HSFREQRANGE_180MBPS	(0x22 << 16)
+#define PHYPLL_HSFREQRANGE_190MBPS	(0x32 << 16)
+#define PHYPLL_HSFREQRANGE_205MBPS	(0x03 << 16)
+#define PHYPLL_HSFREQRANGE_220MBPS	(0x13 << 16)
+#define PHYPLL_HSFREQRANGE_235MBPS	(0x23 << 16)
+#define PHYPLL_HSFREQRANGE_250MBPS	(0x33 << 16)
+#define PHYPLL_HSFREQRANGE_275MBPS	(0x04 << 16)
+#define PHYPLL_HSFREQRANGE_300MBPS	(0x14 << 16)
+#define PHYPLL_HSFREQRANGE_325MBPS	(0x05 << 16)
+#define PHYPLL_HSFREQRANGE_350MBPS	(0x15 << 16)
+#define PHYPLL_HSFREQRANGE_400MBPS	(0x25 << 16)
+#define PHYPLL_HSFREQRANGE_450MBPS	(0x06 << 16)
+#define PHYPLL_HSFREQRANGE_500MBPS	(0x16 << 16)
+#define PHYPLL_HSFREQRANGE_550MBPS	(0x07 << 16)
+#define PHYPLL_HSFREQRANGE_600MBPS	(0x17 << 16)
+#define PHYPLL_HSFREQRANGE_650MBPS	(0x08 << 16)
+#define PHYPLL_HSFREQRANGE_700MBPS	(0x18 << 16)
+#define PHYPLL_HSFREQRANGE_750MBPS	(0x09 << 16)
+#define PHYPLL_HSFREQRANGE_800MBPS	(0x19 << 16)
+#define PHYPLL_HSFREQRANGE_850MBPS	(0x29 << 16)
+#define PHYPLL_HSFREQRANGE_900MBPS	(0x39 << 16)
+#define PHYPLL_HSFREQRANGE_950MBPS	(0x0A << 16)
+#define PHYPLL_HSFREQRANGE_1000MBPS	(0x1A << 16)
+#define PHYPLL_HSFREQRANGE_1050MBPS	(0x2A << 16)
+#define PHYPLL_HSFREQRANGE_1100MBPS	(0x3A << 16)
+#define PHYPLL_HSFREQRANGE_1150MBPS	(0x0B << 16)
+#define PHYPLL_HSFREQRANGE_1200MBPS	(0x1B << 16)
+#define PHYPLL_HSFREQRANGE_1250MBPS	(0x2B << 16)
+#define PHYPLL_HSFREQRANGE_1300MBPS	(0x3B << 16)
+#define PHYPLL_HSFREQRANGE_1350MBPS	(0x0C << 16)
+#define PHYPLL_HSFREQRANGE_1400MBPS	(0x1C << 16)
+#define PHYPLL_HSFREQRANGE_1450MBPS	(0x2C << 16)
+#define PHYPLL_HSFREQRANGE_1500MBPS	(0x3C << 16)
+
+enum rcar_csi2_pads {
+	RCAR_CSI2_SINK,
+	RCAR_CSI2_SOURCE_VC0,
+	RCAR_CSI2_SOURCE_VC1,
+	RCAR_CSI2_SOURCE_VC2,
+	RCAR_CSI2_SOURCE_VC3,
+	RCAR_CSI2_PAD_MAX,
+};
+
+struct rcar_csi2 {
+	struct device *dev;
+	void __iomem *base;
+	spinlock_t lock;
+
+	unsigned short lanes;
+	unsigned char swap[4];
+
+	struct v4l2_subdev subdev;
+	struct media_pad pads[RCAR_CSI2_PAD_MAX];
+	struct v4l2_mbus_framefmt mf;
+};
+
+#define csi_dbg(p, fmt, arg...)		dev_dbg(p->dev, fmt, ##arg)
+#define csi_info(p, fmt, arg...)	dev_info(p->dev, fmt, ##arg)
+#define csi_warn(p, fmt, arg...)	dev_warn(p->dev, fmt, ##arg)
+#define csi_err(p, fmt, arg...)		dev_err(p->dev, fmt, ##arg)
+
+static irqreturn_t rcar_csi2_irq(int irq, void *data)
+{
+	struct rcar_csi2 *priv = data;
+	u32 int_status;
+	unsigned int handled = 0;
+
+	spin_lock(&priv->lock);
+
+	int_status = ioread32(priv->base + INTSTATE_REG);
+	if (!int_status)
+		goto done;
+
+	/* ack interrupts */
+	iowrite32(int_status, priv->base + INTSTATE_REG);
+	handled = 1;
+
+done:
+	spin_unlock(&priv->lock);
+
+	return IRQ_RETVAL(handled);
+
+}
+
+static void rcar_csi2_reset(struct rcar_csi2 *priv)
+{
+	iowrite32(SRST_SRST, priv->base + SRST_REG);
+	udelay(5);
+	iowrite32(0, priv->base + SRST_REG);
+}
+
+static void rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
+{
+	int timeout;
+
+	/* Read the PHY clock lane monitor register (PHCLM). */
+	for (timeout = 100; timeout >= 0; timeout--) {
+		if (ioread32(priv->base + PHCLM_REG) & 0x01) {
+			csi_dbg(priv, "Detected the PHY clock lane\n");
+			break;
+		}
+		msleep(20);
+	}
+	if (!timeout)
+		csi_err(priv, "Timeout of reading the PHY clock lane\n");
+
+
+	/* Read the PHY data lane monitor register (PHDLM). */
+	for (timeout = 100; timeout >= 0; timeout--) {
+		if (ioread32(priv->base + PHDLM_REG) & 0x01) {
+			csi_dbg(priv, "Detected the PHY data lane\n");
+			break;
+		}
+		msleep(20);
+	}
+	if (!timeout)
+		csi_err(priv, "Timeout of reading the PHY data lane\n");
+
+}
+
+static int rcar_csi2_start(struct rcar_csi2 *priv)
+{
+	u32 fld, phycnt, phypll, vcdt, vcdt2, tmp, pixels;
+	int i;
+
+	csi_dbg(priv, "Input size (%dx%d%c)\n", priv->mf.width, priv->mf.height,
+		priv->mf.field == V4L2_FIELD_NONE ? 'p' : 'i');
+
+	vcdt = vcdt2 = 0;
+	for (i = 0; i < priv->lanes; i++) {
+		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON;
+
+		switch (priv->mf.code) {
+		case MEDIA_BUS_FMT_RGB888_1X24:
+			/* 24 == RGB888 */
+			tmp |= 0x24;
+			break;
+		case MEDIA_BUS_FMT_UYVY8_1X16:
+		case MEDIA_BUS_FMT_UYVY8_2X8:
+		case MEDIA_BUS_FMT_YUYV10_2X10:
+			/* 1E == YUV422 8-bit */
+			tmp |= 0x1e;
+			break;
+		default:
+			csi_warn(priv,
+				 "Unknown media bus format, try it anyway\n");
+			break;
+		}
+
+		/* Store in correct reg and offset */
+		if (i < 2)
+			vcdt |= tmp << ((i % 2) * 16);
+		else
+			vcdt2 |= tmp << ((i % 2) * 16);
+	}
+
+	switch (priv->lanes) {
+	case 1:
+		fld = FLD_FLD_NUM(1) | FLD_FLD_EN;
+		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
+		phypll = PHYPLL_HSFREQRANGE_400MBPS;
+		break;
+	case 4:
+		fld = FLD_FLD_NUM(2) | FLD_FLD_EN4 | FLD_FLD_EN3 |
+			FLD_FLD_EN2 | FLD_FLD_EN;
+		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 |
+			PHYCNT_ENABLE_2 | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
+
+		/* Calculate MBPS per lane, assume 32 bits per pixel at 60Hz */
+		pixels = (priv->mf.width * priv->mf.height) /
+			(priv->mf.field == V4L2_FIELD_NONE ? 1 : 2);
+		if (pixels <= 640 * 480)
+			phypll = PHYPLL_HSFREQRANGE_100MBPS;
+		else if (pixels <= 720 * 576)
+			phypll = PHYPLL_HSFREQRANGE_190MBPS;
+		else if (pixels <= 1280 * 720)
+			phypll = PHYPLL_HSFREQRANGE_450MBPS;
+		else if (pixels <= 1920 * 1080)
+			phypll = PHYPLL_HSFREQRANGE_900MBPS;
+		else
+			goto error;
+
+		break;
+	default:
+		goto error;
+	}
+
+	/* Init */
+	iowrite32(TREF_TREF, priv->base + TREF_REG);
+	rcar_csi2_reset(priv);
+	iowrite32(0, priv->base + PHTC_REG);
+
+	/* Configure */
+	iowrite32(fld, priv->base + FLD_REG);
+	iowrite32(vcdt, priv->base + VCDT_REG);
+	iowrite32(vcdt2, priv->base + VCDT2_REG);
+	iowrite32(LSWAP_L0SEL(priv->swap[0]) | LSWAP_L1SEL(priv->swap[1]) |
+		  LSWAP_L2SEL(priv->swap[2]) | LSWAP_L3SEL(priv->swap[3]),
+		  priv->base + LSWAP_REG);
+
+	/* Start */
+	iowrite32(phypll, priv->base + PHYPLL_REG);
+	iowrite32(phycnt, priv->base + PHYCNT_REG);
+	iowrite32(LINKCNT_MONITOR_EN | LINKCNT_REG_MONI_PACT_EN |
+		  LINKCNT_ICLK_NONSTOP, priv->base + LINKCNT_REG);
+	iowrite32(phycnt | PHYCNT_SHUTDOWNZ, priv->base + PHYCNT_REG);
+	iowrite32(phycnt | PHYCNT_SHUTDOWNZ | PHYCNT_RSTZ,
+		  priv->base + PHYCNT_REG);
+
+	rcar_csi2_wait_phy_start(priv);
+
+	return 0;
+error:
+	csi_err(priv, "Unsupported resolution (%dx%d%c)\n",
+		priv->mf.width, priv->mf.height,
+		priv->mf.field == V4L2_FIELD_NONE ? 'p' : 'i');
+
+	return -EINVAL;
+}
+
+static void rcar_csi2_stop(struct rcar_csi2 *priv)
+{
+	iowrite32(0, priv->base + PHYCNT_REG);
+
+	rcar_csi2_reset(priv);
+}
+
+static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	if (enable)
+		return rcar_csi2_start(priv);
+
+	rcar_csi2_stop(priv);
+
+	return 0;
+}
+
+static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_pad_config *cfg,
+				    struct v4l2_subdev_format *format)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	if (format->pad != RCAR_CSI2_SINK)
+		return -EINVAL;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
+		priv->mf = format->format;
+
+	return 0;
+}
+
+static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_pad_config *cfg,
+				    struct v4l2_subdev_format *format)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	if (format->pad != RCAR_CSI2_SINK)
+		return -EINVAL;
+
+	format->format = priv->mf;
+
+	return 0;
+}
+
+static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	if (on)
+		pm_runtime_get_sync(priv->dev);
+	else
+		pm_runtime_put_sync(priv->dev);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
+	.s_stream = rcar_csi2_s_stream,
+};
+
+static struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
+	.s_power = rcar_csi2_s_power,
+};
+
+static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
+	.set_fmt = rcar_csi2_set_pad_format,
+	.get_fmt = rcar_csi2_get_pad_format,
+};
+
+static struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
+	.video	= &rcar_csi2_video_ops,
+	.core	= &rcar_csi2_subdev_core_ops,
+	.pad	= &rcar_csi2_pad_ops,
+};
+
+/* -----------------------------------------------------------------------------
+ * Platform Device Driver
+ */
+
+static const struct of_device_id rcar_csi2_of_table[] = {
+	{ .compatible = "renesas,r8a7795-csi2" },
+	{ .compatible = "renesas,r8a7796-csi2" },
+	{ .compatible = "renesas,rcar-gen3-csi2" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
+
+static int rcar_csi2_parse_dt(struct rcar_csi2 *priv)
+{
+	struct v4l2_of_endpoint v4l2_ep;
+	struct device_node *ep;
+	int i, n, ret;
+
+	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
+	if (!ep)
+		return -EINVAL;
+
+	ret = v4l2_of_parse_endpoint(ep, &v4l2_ep);
+	of_node_put(ep);
+	if (ret) {
+		csi_err(priv, "Could not parse v4l2 endpoint\n");
+		return -EINVAL;
+	}
+
+	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
+		csi_err(priv, "Unsupported media bus type for %s\n",
+			of_node_full_name(ep));
+		return -EINVAL;
+	}
+
+	switch (v4l2_ep.bus.mipi_csi2.num_data_lanes) {
+	case 1:
+	case 4:
+		priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
+		break;
+	default:
+		csi_err(priv, "Unsupported number of lanes\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < 4; i++)
+		priv->swap[i] = i;
+
+	for (i = 0; i < priv->lanes; i++) {
+		/* Check for valid lane number */
+		if (v4l2_ep.bus.mipi_csi2.data_lanes[i] < 1 ||
+		    v4l2_ep.bus.mipi_csi2.data_lanes[i] > 4) {
+			csi_err(priv, "data lanes must be in 1-4 range\n");
+			return -EINVAL;
+		}
+
+		/* Use lane numbers 0-3 internally */
+		priv->swap[i] = v4l2_ep.bus.mipi_csi2.data_lanes[i] - 1;
+
+
+	}
+
+	/* Make sure there are no duplicates */
+	for (i = 0; i < priv->lanes; i++) {
+		for (n = i + 1; n < priv->lanes; n++) {
+			if (priv->swap[i] == priv->swap[n]) {
+				csi_err(priv,
+					"Requested swapping not possible\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
+				     struct platform_device *pdev)
+{
+	struct resource *mem;
+	int irq;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem)
+		return -ENODEV;
+
+	priv->base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (!irq)
+		return -ENODEV;
+
+	return devm_request_irq(&pdev->dev, irq, rcar_csi2_irq, IRQF_SHARED,
+				dev_name(&pdev->dev), priv);
+}
+
+static int rcar_csi2_probe(struct platform_device *pdev)
+{
+	struct rcar_csi2 *priv;
+	unsigned int i;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(struct rcar_csi2), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+
+	priv->dev = &pdev->dev;
+	spin_lock_init(&priv->lock);
+
+	ret = rcar_csi2_parse_dt(priv);
+	if (ret)
+		return ret;
+
+	ret = rcar_csi2_probe_resources(priv, pdev);
+	if (ret) {
+		csi_err(priv, "Failed to get resources\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	priv->subdev.owner = THIS_MODULE;
+	priv->subdev.dev = &pdev->dev;
+	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
+	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
+	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.%s",
+		 KBUILD_MODNAME, dev_name(&pdev->dev));
+
+	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+	priv->subdev.entity.flags |= MEDIA_ENT_F_ATV_DECODER;
+
+	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
+	for (i = RCAR_CSI2_SOURCE_VC0; i < RCAR_CSI2_PAD_MAX; i++)
+		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
+
+	ret = media_entity_pads_init(&priv->subdev.entity, RCAR_CSI2_PAD_MAX,
+				     priv->pads);
+	if (ret)
+		return ret;
+
+	ret = v4l2_async_register_subdev(&priv->subdev);
+	if (ret < 0)
+		return ret;
+
+	pm_runtime_enable(&pdev->dev);
+
+	csi_info(priv, "%d lanes found\n", priv->lanes);
+
+	return 0;
+}
+
+static int rcar_csi2_remove(struct platform_device *pdev)
+{
+	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
+
+	v4l2_async_unregister_subdev(&priv->subdev);
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver __refdata rcar_csi2_pdrv = {
+	.remove	= rcar_csi2_remove,
+	.probe	= rcar_csi2_probe,
+	.driver	= {
+		.name	= "rcar-csi2",
+		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
+	},
+};
+
+module_platform_driver(rcar_csi2_pdrv);
+
+MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
+MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 driver");
+MODULE_LICENSE("GPL v2");