From 712d6617d0a29dc4d4da361247720cdf156ae7bb Mon Sep 17 00:00:00 2001 From: Vadim Pasternak Date: Mon, 23 Aug 2021 17:45:04 +0300 Subject: [PATCH] i2c: mlxcpld: Allow flexible polling time setting for I2C transactions Allow polling time setting according to I2C frequency supported across the system. For base frequency 400 KHz and 1 MHz set polling time is set four times less than for system with base frequency 100KHz. Signed-off-by: Vadim Pasternak Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-mlxcpld.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-mlxcpld.c b/drivers/i2c/busses/i2c-mlxcpld.c index 615f0a98..56aa424 100644 --- a/drivers/i2c/busses/i2c-mlxcpld.c +++ b/drivers/i2c/busses/i2c-mlxcpld.c @@ -73,6 +73,7 @@ struct mlxcpld_i2c_priv { struct mlxcpld_i2c_curr_xfer xfer; struct device *dev; bool smbus_block; + int polling_time; }; static void mlxcpld_i2c_lpc_write_buf(u8 *data, u8 len, u32 addr) @@ -267,8 +268,8 @@ static int mlxcpld_i2c_wait_for_free(struct mlxcpld_i2c_priv *priv) do { if (!mlxcpld_i2c_check_busy(priv)) break; - usleep_range(MLXCPLD_I2C_POLL_TIME / 2, MLXCPLD_I2C_POLL_TIME); - timeout += MLXCPLD_I2C_POLL_TIME; + usleep_range(priv->polling_time / 2, priv->polling_time); + timeout += priv->polling_time; } while (timeout <= MLXCPLD_I2C_XFER_TO); if (timeout > MLXCPLD_I2C_XFER_TO) @@ -288,10 +289,10 @@ static int mlxcpld_i2c_wait_for_tc(struct mlxcpld_i2c_priv *priv) u8 datalen, val; do { - usleep_range(MLXCPLD_I2C_POLL_TIME / 2, MLXCPLD_I2C_POLL_TIME); + usleep_range(priv->polling_time / 2, priv->polling_time); if (!mlxcpld_i2c_check_status(priv, &status)) break; - timeout += MLXCPLD_I2C_POLL_TIME; + timeout += priv->polling_time; } while (status == 0 && timeout < MLXCPLD_I2C_XFER_TO); switch (status) { @@ -498,9 +499,11 @@ mlxcpld_i2c_set_frequency(struct mlxcpld_i2c_priv *priv, switch ((regval & data->mask) >> data->bit) { case MLXCPLD_I2C_FREQ_1000KHZ: freq = MLXCPLD_I2C_FREQ_1000KHZ_SET; + priv->polling_time /= 4; break; case MLXCPLD_I2C_FREQ_400KHZ: freq = MLXCPLD_I2C_FREQ_400KHZ_SET; + priv->polling_time /= 4; break; default: return 0; @@ -527,6 +530,7 @@ static int mlxcpld_i2c_probe(struct platform_device *pdev) priv->dev = &pdev->dev; priv->base_addr = MLXPLAT_CPLD_LPC_I2C_BASE_ADDR; + priv->polling_time = MLXCPLD_I2C_POLL_TIME; /* Set I2C bus frequency if platform data provides this info. */ pdata = dev_get_platdata(&pdev->dev); -- 2.7.4