From 0d1ee1f265cf9730feb214ddd18bc430c0800e8b Mon Sep 17 00:00:00 2001 From: Tim Harvey Date: Tue, 10 Sep 2013 21:42:29 +0200 Subject: [PATCH] i2c: imx: retry on NAK In case of busy i2c try again to get ACK. Signed-off-by: Tim Harvey Tested-by: Luka Perkov --- drivers/i2c/busses/i2c-imx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -62,6 +62,7 @@ /* Default value */ #define IMX_I2C_BIT_RATE 100000 /* 100kHz */ +#define IMX_I2C_MAX_RETRIES 3 /* number of retries to attempt */ /* IMX I2C registers */ #define IMX_I2C_IADR 0x00 /* i2c slave address */ @@ -198,7 +199,7 @@ static int i2c_imx_acked(struct imx_i2c_ { if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) { dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); - return -EIO; /* No ACK */ + return -EAGAIN; /* try again */ } dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__); @@ -533,6 +534,7 @@ static int __init i2c_imx_probe(struct p i2c_imx->adapter.dev.parent = &pdev->dev; i2c_imx->adapter.nr = pdev->id; i2c_imx->adapter.dev.of_node = pdev->dev.of_node; + i2c_imx->adapter.retries = IMX_I2C_MAX_RETRIES; i2c_imx->base = base; pinctrl = devm_pinctrl_get_select_default(&pdev->dev);