[PATCH v3 0/2] v4l2-cci: little-endian registers

[PATCH v3 0/2] v4l2-cci: little-endian registers

[Alexander Stein]

Hi,

after the discussions at [1] and [2], this series adds proper support for
little-endian encoded registers.
Patch 1 adds the infrastructure and patch 2 fixes imx290 driver.
As v6.6 was released with imx290 broken, both should be added to stable.

I just focues on fixing the endianess issue. Any future cleanup as already
discussed is discarded for now.

Changes in v3:
* Explicitly name IMX290 as an example sensor using little-endian registers
* Move CCI_REG_LE to first location on register definition
* Use unsigned numbers for registers width definition
* Added Laurent's and Hans' R-b

Changes in v2:
* Add proper Fixes/CC tags to both patches
* Add little-endian support for cci_read()

Best regards,
Alexander

[1] https://lore.kernel.org/linux-media/20231030173637.GA2977515@gnbcxd0016.gnb.st.com/
[2] https://lore.kernel.org/linux-media/ZUIuNDTJAN_fz3q6@kekkonen.localdomain/

Alexander Stein (2):
  media: v4l2-cci: Add support for little-endian encoded registers
  media: i2c: imx290: Properly encode registers as little-endian

 drivers/media/i2c/imx290.c         | 42 ++++++++++++++--------------
 drivers/media/v4l2-core/v4l2-cci.c | 44 ++++++++++++++++++++++++------
 include/media/v4l2-cci.h           |  5 ++++
 3 files changed, 62 insertions(+), 29 deletions(-)

-- 
2.34.1

[PATCH v3 1/2] media: v4l2-cci: Add support for little-endian encoded registers

[Alexander Stein]

Some sensors, e.g. Sony IMX290, are using little-endian registers. Add
support for those by encoding the endianess into Bit 20 of the register
address.

Fixes: af73323b97702 ("media: imx290: Convert to new CCI register access helpers")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/v4l2-core/v4l2-cci.c | 44 ++++++++++++++++++++++++------
 include/media/v4l2-cci.h           |  5 ++++
 2 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-cci.c b/drivers/media/v4l2-core/v4l2-cci.c
index bc2dbec019b04..673637b67bf67 100644
--- a/drivers/media/v4l2-core/v4l2-cci.c
+++ b/drivers/media/v4l2-core/v4l2-cci.c
@@ -18,6 +18,7 @@
 
 int cci_read(struct regmap *map, u32 reg, u64 *val, int *err)
 {
+	bool little_endian;
 	unsigned int len;
 	u8 buf[8];
 	int ret;
@@ -25,6 +26,7 @@ int cci_read(struct regmap *map, u32 reg, u64 *val, int *err)
 	if (err && *err)
 		return *err;
 
+	little_endian = reg & CCI_REG_LE;
 	len = FIELD_GET(CCI_REG_WIDTH_MASK, reg);
 	reg = FIELD_GET(CCI_REG_ADDR_MASK, reg);
 
@@ -40,16 +42,28 @@ int cci_read(struct regmap *map, u32 reg, u64 *val, int *err)
 		*val = buf[0];
 		break;
 	case 2:
-		*val = get_unaligned_be16(buf);
+		if (little_endian)
+			*val = get_unaligned_le16(buf);
+		else
+			*val = get_unaligned_be16(buf);
 		break;
 	case 3:
-		*val = get_unaligned_be24(buf);
+		if (little_endian)
+			*val = get_unaligned_le24(buf);
+		else
+			*val = get_unaligned_be24(buf);
 		break;
 	case 4:
-		*val = get_unaligned_be32(buf);
+		if (little_endian)
+			*val = get_unaligned_le32(buf);
+		else
+			*val = get_unaligned_be32(buf);
 		break;
 	case 8:
-		*val = get_unaligned_be64(buf);
+		if (little_endian)
+			*val = get_unaligned_le64(buf);
+		else
+			*val = get_unaligned_be64(buf);
 		break;
 	default:
 		dev_err(regmap_get_device(map), "Error invalid reg-width %u for reg 0x%04x\n",
@@ -68,6 +82,7 @@ EXPORT_SYMBOL_GPL(cci_read);
 
 int cci_write(struct regmap *map, u32 reg, u64 val, int *err)
 {
+	bool little_endian;
 	unsigned int len;
 	u8 buf[8];
 	int ret;
@@ -75,6 +90,7 @@ int cci_write(struct regmap *map, u32 reg, u64 val, int *err)
 	if (err && *err)
 		return *err;
 
+	little_endian = reg & CCI_REG_LE;
 	len = FIELD_GET(CCI_REG_WIDTH_MASK, reg);
 	reg = FIELD_GET(CCI_REG_ADDR_MASK, reg);
 
@@ -83,16 +99,28 @@ int cci_write(struct regmap *map, u32 reg, u64 val, int *err)
 		buf[0] = val;
 		break;
 	case 2:
-		put_unaligned_be16(val, buf);
+		if (little_endian)
+			put_unaligned_le16(val, buf);
+		else
+			put_unaligned_be16(val, buf);
 		break;
 	case 3:
-		put_unaligned_be24(val, buf);
+		if (little_endian)
+			put_unaligned_le24(val, buf);
+		else
+			put_unaligned_be24(val, buf);
 		break;
 	case 4:
-		put_unaligned_be32(val, buf);
+		if (little_endian)
+			put_unaligned_le32(val, buf);
+		else
+			put_unaligned_be32(val, buf);
 		break;
 	case 8:
-		put_unaligned_be64(val, buf);
+		if (little_endian)
+			put_unaligned_le64(val, buf);
+		else
+			put_unaligned_be64(val, buf);
 		break;
 	default:
 		dev_err(regmap_get_device(map), "Error invalid reg-width %u for reg 0x%04x\n",
diff --git a/include/media/v4l2-cci.h b/include/media/v4l2-cci.h
index 0f6803e4b17e9..80cbb5cb70fa5 100644
--- a/include/media/v4l2-cci.h
+++ b/include/media/v4l2-cci.h
@@ -32,12 +32,17 @@ struct cci_reg_sequence {
 #define CCI_REG_ADDR_MASK		GENMASK(15, 0)
 #define CCI_REG_WIDTH_SHIFT		16
 #define CCI_REG_WIDTH_MASK		GENMASK(19, 16)
+#define CCI_REG_LE			BIT(20)
 
 #define CCI_REG8(x)			((1 << CCI_REG_WIDTH_SHIFT) | (x))
 #define CCI_REG16(x)			((2 << CCI_REG_WIDTH_SHIFT) | (x))
 #define CCI_REG24(x)			((3 << CCI_REG_WIDTH_SHIFT) | (x))
 #define CCI_REG32(x)			((4 << CCI_REG_WIDTH_SHIFT) | (x))
 #define CCI_REG64(x)			((8 << CCI_REG_WIDTH_SHIFT) | (x))
+#define CCI_REG16_LE(x)			(CCI_REG_LE | (2U << CCI_REG_WIDTH_SHIFT) | (x))
+#define CCI_REG24_LE(x)			(CCI_REG_LE | (3U << CCI_REG_WIDTH_SHIFT) | (x))
+#define CCI_REG32_LE(x)			(CCI_REG_LE | (4U << CCI_REG_WIDTH_SHIFT) | (x))
+#define CCI_REG64_LE(x)			(CCI_REG_LE | (8U << CCI_REG_WIDTH_SHIFT) | (x))
 
 /**
  * cci_read() - Read a value from a single CCI register
-- 
2.34.1

[PATCH v3 2/2] media: i2c: imx290: Properly encode registers as little-endian

[Alexander Stein]

The conversion to CCI also converted the multi-byte register access to
big-endian. Correct the register definition by using the correct
little-endian ones.

Fixes: af73323b97702 ("media: imx290: Convert to new CCI register access helpers")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/i2c/imx290.c | 42 +++++++++++++++++++-------------------
 1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
index 29098612813cb..c6fea5837a19f 100644
--- a/drivers/media/i2c/imx290.c
+++ b/drivers/media/i2c/imx290.c
@@ -41,18 +41,18 @@
 #define IMX290_WINMODE_720P				(1 << 4)
 #define IMX290_WINMODE_CROP				(4 << 4)
 #define IMX290_FR_FDG_SEL				CCI_REG8(0x3009)
-#define IMX290_BLKLEVEL					CCI_REG16(0x300a)
+#define IMX290_BLKLEVEL					CCI_REG16_LE(0x300a)
 #define IMX290_GAIN					CCI_REG8(0x3014)
-#define IMX290_VMAX					CCI_REG24(0x3018)
+#define IMX290_VMAX					CCI_REG24_LE(0x3018)
 #define IMX290_VMAX_MAX					0x3ffff
-#define IMX290_HMAX					CCI_REG16(0x301c)
+#define IMX290_HMAX					CCI_REG16_LE(0x301c)
 #define IMX290_HMAX_MAX					0xffff
-#define IMX290_SHS1					CCI_REG24(0x3020)
+#define IMX290_SHS1					CCI_REG24_LE(0x3020)
 #define IMX290_WINWV_OB					CCI_REG8(0x303a)
-#define IMX290_WINPV					CCI_REG16(0x303c)
-#define IMX290_WINWV					CCI_REG16(0x303e)
-#define IMX290_WINPH					CCI_REG16(0x3040)
-#define IMX290_WINWH					CCI_REG16(0x3042)
+#define IMX290_WINPV					CCI_REG16_LE(0x303c)
+#define IMX290_WINWV					CCI_REG16_LE(0x303e)
+#define IMX290_WINPH					CCI_REG16_LE(0x3040)
+#define IMX290_WINWH					CCI_REG16_LE(0x3042)
 #define IMX290_OUT_CTRL					CCI_REG8(0x3046)
 #define IMX290_ODBIT_10BIT				(0 << 0)
 #define IMX290_ODBIT_12BIT				(1 << 0)
@@ -78,28 +78,28 @@
 #define IMX290_ADBIT2					CCI_REG8(0x317c)
 #define IMX290_ADBIT2_10BIT				0x12
 #define IMX290_ADBIT2_12BIT				0x00
-#define IMX290_CHIP_ID					CCI_REG16(0x319a)
+#define IMX290_CHIP_ID					CCI_REG16_LE(0x319a)
 #define IMX290_ADBIT3					CCI_REG8(0x31ec)
 #define IMX290_ADBIT3_10BIT				0x37
 #define IMX290_ADBIT3_12BIT				0x0e
 #define IMX290_REPETITION				CCI_REG8(0x3405)
 #define IMX290_PHY_LANE_NUM				CCI_REG8(0x3407)
 #define IMX290_OPB_SIZE_V				CCI_REG8(0x3414)
-#define IMX290_Y_OUT_SIZE				CCI_REG16(0x3418)
-#define IMX290_CSI_DT_FMT				CCI_REG16(0x3441)
+#define IMX290_Y_OUT_SIZE				CCI_REG16_LE(0x3418)
+#define IMX290_CSI_DT_FMT				CCI_REG16_LE(0x3441)
 #define IMX290_CSI_DT_FMT_RAW10				0x0a0a
 #define IMX290_CSI_DT_FMT_RAW12				0x0c0c
 #define IMX290_CSI_LANE_MODE				CCI_REG8(0x3443)
-#define IMX290_EXTCK_FREQ				CCI_REG16(0x3444)
-#define IMX290_TCLKPOST					CCI_REG16(0x3446)
-#define IMX290_THSZERO					CCI_REG16(0x3448)
-#define IMX290_THSPREPARE				CCI_REG16(0x344a)
-#define IMX290_TCLKTRAIL				CCI_REG16(0x344c)
-#define IMX290_THSTRAIL					CCI_REG16(0x344e)
-#define IMX290_TCLKZERO					CCI_REG16(0x3450)
-#define IMX290_TCLKPREPARE				CCI_REG16(0x3452)
-#define IMX290_TLPX					CCI_REG16(0x3454)
-#define IMX290_X_OUT_SIZE				CCI_REG16(0x3472)
+#define IMX290_EXTCK_FREQ				CCI_REG16_LE(0x3444)
+#define IMX290_TCLKPOST					CCI_REG16_LE(0x3446)
+#define IMX290_THSZERO					CCI_REG16_LE(0x3448)
+#define IMX290_THSPREPARE				CCI_REG16_LE(0x344a)
+#define IMX290_TCLKTRAIL				CCI_REG16_LE(0x344c)
+#define IMX290_THSTRAIL					CCI_REG16_LE(0x344e)
+#define IMX290_TCLKZERO					CCI_REG16_LE(0x3450)
+#define IMX290_TCLKPREPARE				CCI_REG16_LE(0x3452)
+#define IMX290_TLPX					CCI_REG16_LE(0x3454)
+#define IMX290_X_OUT_SIZE				CCI_REG16_LE(0x3472)
 #define IMX290_INCKSEL7					CCI_REG8(0x3480)
 
 #define IMX290_PGCTRL_REGEN				BIT(0)
-- 
2.34.1

Re: [PATCH v3 0/2] v4l2-cci: little-endian registers

[Sakari Ailus]

On Thu, Nov 02, 2023 at 10:50:46AM +0100, Alexander Stein wrote:
> Hi,
> 
> after the discussions at [1] and [2], this series adds proper support for
> little-endian encoded registers.
> Patch 1 adds the infrastructure and patch 2 fixes imx290 driver.
> As v6.6 was released with imx290 broken, both should be added to stable.
> 
> I just focues on fixing the endianess issue. Any future cleanup as already
> discussed is discarded for now.
> 
> Changes in v3:
> * Explicitly name IMX290 as an example sensor using little-endian registers
> * Move CCI_REG_LE to first location on register definition
> * Use unsigned numbers for registers width definition
> * Added Laurent's and Hans' R-b

Thanks, Alexander!

I'll submit these as fixes when we have rc1 available.

-- 
Sakari Ailus