Hi,
On 15/01/2025 16:17, Sakari Ailus wrote:
Moi,
On Fri, Jan 10, 2025 at 11:14:07AM +0200, Tomi Valkeinen wrote:
From: Jai Luthra <jai.luthra@xxxxxxxxxxxxxxxx>
On the I2C bus for remote clients (sensors), by default the watchdog
timer expires in 1s. To allow for a quicker system bring-up time, TI
recommends to speed it up to 50us [1].
[1]: Section 7.3.1.1 - https://www.ti.com/lit/gpn/ds90ub953-q1
Signed-off-by: Jai Luthra <jai.luthra@xxxxxxxxxxxxxxxx>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
drivers/media/i2c/ds90ub953.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c
index 99a4852b9381..6c36980e8beb 100644
--- a/drivers/media/i2c/ds90ub953.c
+++ b/drivers/media/i2c/ds90ub953.c
@@ -54,6 +54,10 @@
#define UB953_REG_CLKOUT_CTRL0 0x06
#define UB953_REG_CLKOUT_CTRL1 0x07
+#define UB953_REG_I2C_CONTROL2 0x0a
+#define UB953_REG_I2C_CONTROL2_SDA_OUTPUT_SETUP_SHIFT 4
+#define UB953_REG_I2C_CONTROL2_BUS_SPEEDUP BIT(1)
+
#define UB953_REG_SCL_HIGH_TIME 0x0b
#define UB953_REG_SCL_LOW_TIME 0x0c
@@ -1320,6 +1324,13 @@ static int ub953_hw_init(struct ub953_data *priv)
if (ret)
return ret;
+ v = 0;
+ v |= 1 << UB953_REG_I2C_CONTROL2_SDA_OUTPUT_SETUP_SHIFT;
BIT()? Or at least 1U <<< ...;.
It's a three-bit field, the value just happens to be 1. What's wrong
with 1 << SHIFT?
+ v |= UB953_REG_I2C_CONTROL2_BUS_SPEEDUP;
+ ret = ub953_write(priv, UB953_REG_I2C_CONTROL2, v, NULL);
I'd just do this without a temporary variable. If you prefer to keep it, do
assign the first calculated value there first and remove the assignment to
zero.
I think we can do without.
+ if (ret)
+ return ret;
No need for this.
No, but it keeps the code structure consistent and allows easy
future/debug modifications.
Tomi
