[PATCH v3 07/11] i2c: nomadik: fetch i2c-transfer-timeout-us property from devicetree

From: Théo Lebrun
Date: Wed Mar 06 2024 - 13:07:13 EST


Allow overriding the default timeout value (200ms) from devicetree,
using the generic i2c-transfer-timeout-us property.

The i2c_adapter->timeout field is an unaccurate jiffies amount;
i2c-nomadik uses hrtimers for timeouts below one jiffy.

Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxx>
Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
---
drivers/i2c/busses/i2c-nomadik.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 020beb8ffa17..2e738b18677e 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -975,6 +975,8 @@ static const struct i2c_algorithm nmk_i2c_algo = {
static void nmk_i2c_of_probe(struct device_node *np,
struct nmk_i2c_dev *priv)
{
+ u32 timeout_usecs;
+
/* Default to 100 kHz if no frequency is given in the node */
if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq))
priv->clk_freq = I2C_MAX_STANDARD_MODE_FREQ;
@@ -986,7 +988,12 @@ static void nmk_i2c_of_probe(struct device_node *np,
priv->sm = I2C_FREQ_MODE_FAST;
priv->tft = 1; /* Tx FIFO threshold */
priv->rft = 8; /* Rx FIFO threshold */
- priv->timeout_usecs = 200 * USEC_PER_MSEC; /* Slave response timeout */
+
+ /* Slave response timeout */
+ if (!of_property_read_u32(np, "i2c-transfer-timeout-us", &timeout_usecs))
+ priv->timeout_usecs = timeout_usecs;
+ else
+ priv->timeout_usecs = 200 * USEC_PER_MSEC;
}

static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)

--
2.44.0