brcm2708: organize kernel patches

[openwrt/openwrt.git] / target / linux / brcm2708 / patches-4.19 / 950-0176-media-tc358743-Check-I2C-succeeded-during-probe.patch

diff --git a/target/linux/brcm2708/patches-4.19/950-0176-media-tc358743-Check-I2C-succeeded-during-probe.patch b/target/linux/brcm2708/patches-4.19/950-0176-media-tc358743-Check-I2C-succeeded-during-probe.patch
new file mode 100644 (file)
index 0000000..6cb1134
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0176-media-tc358743-Check-I2C-succeeded-during-probe.patch
@@ -0,0 +1,98 @@
+From 6e089b7c2526037b0eaf9ecaed4d38957f33c19c Mon Sep 17 00:00:00 2001
+From: Dave Stevenson <dave.stevenson@raspberrypi.org>
+Date: Wed, 31 Oct 2018 14:57:34 +0000
+Subject: [PATCH] media: tc358743: Check I2C succeeded during probe.
+
+The probe for the TC358743 reads the CHIPID register from
+the device and compares it to the expected value of 0.
+If the I2C request fails then that also returns 0, so
+the driver loads thinking that the device is there.
+
+Generally I2C communications are reliable so there is
+limited need to check the return value on every transfer,
+therefore only amend the one read during probe to check
+for I2C errors.
+
+Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
+---
+ drivers/media/i2c/tc358743.c | 27 +++++++++++++++++++++++----
+ 1 file changed, 23 insertions(+), 4 deletions(-)
+
+--- a/drivers/media/i2c/tc358743.c
++++ b/drivers/media/i2c/tc358743.c
+@@ -110,7 +110,7 @@ static inline struct tc358743_state *to_
+ 
+ /* --------------- I2C --------------- */
+ 
+-static void i2c_rd(struct v4l2_subdev *sd, u16 reg, u8 *values, u32 n)
++static int i2c_rd(struct v4l2_subdev *sd, u16 reg, u8 *values, u32 n)
+ {
+       struct tc358743_state *state = to_state(sd);
+       struct i2c_client *client = state->i2c_client;
+@@ -136,6 +136,7 @@ static void i2c_rd(struct v4l2_subdev *s
+               v4l2_err(sd, "%s: reading register 0x%x from 0x%x failed\n",
+                               __func__, reg, client->addr);
+       }
++      return err != ARRAY_SIZE(msgs);
+ }
+ 
+ static void i2c_wr(struct v4l2_subdev *sd, u16 reg, u8 *values, u32 n)
+@@ -192,15 +193,24 @@ static void i2c_wr(struct v4l2_subdev *s
+       }
+ }
+ 
+-static noinline u32 i2c_rdreg(struct v4l2_subdev *sd, u16 reg, u32 n)
++static noinline u32 i2c_rdreg_err(struct v4l2_subdev *sd, u16 reg, u32 n,
++                                int *err)
+ {
++      int error;
+       __le32 val = 0;
+ 
+-      i2c_rd(sd, reg, (u8 __force *)&val, n);
++      error = i2c_rd(sd, reg, (u8 __force *)&val, n);
++      if (err)
++              *err = error;
+ 
+       return le32_to_cpu(val);
+ }
+ 
++static inline u32 i2c_rdreg(struct v4l2_subdev *sd, u16 reg, u32 n)
++{
++      return i2c_rdreg_err(sd, reg, n, NULL);
++}
++
+ static noinline void i2c_wrreg(struct v4l2_subdev *sd, u16 reg, u32 val, u32 n)
+ {
+       __le32 raw = cpu_to_le32(val);
+@@ -229,6 +239,13 @@ static u16 i2c_rd16(struct v4l2_subdev *
+       return i2c_rdreg(sd, reg, 2);
+ }
+ 
++static int i2c_rd16_err(struct v4l2_subdev *sd, u16 reg, u16 *value)
++{
++      int err;
++      *value = i2c_rdreg_err(sd, reg, 2, &err);
++      return err;
++}
++
+ static void i2c_wr16(struct v4l2_subdev *sd, u16 reg, u16 val)
+ {
+       i2c_wrreg(sd, reg, val, 2);
+@@ -2054,6 +2071,7 @@ static int tc358743_probe(struct i2c_cli
+       struct tc358743_platform_data *pdata = client->dev.platform_data;
+       struct v4l2_subdev *sd;
+       u16 irq_mask = MASK_HDMI_MSK | MASK_CSI_MSK;
++      u16 chipid;
+       int err;
+ 
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+@@ -2086,7 +2104,8 @@ static int tc358743_probe(struct i2c_cli
+       sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_HAS_EVENTS;
+ 
+       /* i2c access */
+-      if ((i2c_rd16(sd, CHIPID) & MASK_CHIPID) != 0) {
++      if (i2c_rd16_err(sd, CHIPID, &chipid) ||
++          (chipid & MASK_CHIPID) != 0) {
+               v4l2_info(sd, "not a TC358743 on address 0x%x\n",
+                         client->addr << 1);
+               return -ENODEV;