From d9f52281bc09bd49374486f5e21fad7b8d3a5b3c Mon Sep 17 00:00:00 2001 From: Austin Christ Date: Thu, 10 May 2018 10:13:57 -0600 Subject: i2c: qup: Add command-line parameter to override SCL frequency Add a module parameter to override SCL frequency provided by firmware. This can be useful when testing spec compliance for I2C modes or when debugging issues across multiple operating frequencies. Signed-off-by: Austin Christ Reviewed-by: Sricharan R Reviewed-by: Andy Gross Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-qup.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'drivers/i2c/busses') diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c index f87f29f5be65..c1bbeaae2095 100644 --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -155,6 +155,10 @@ /* TAG length for DATA READ in RX FIFO */ #define READ_RX_TAGS_LEN 2 +static unsigned int scl_freq; +module_param_named(scl_freq, scl_freq, uint, 0444); +MODULE_PARM_DESC(scl_freq, "SCL frequency override"); + /* * count: no of blocks * pos: current block number @@ -1682,10 +1686,15 @@ static int qup_i2c_probe(struct platform_device *pdev) init_completion(&qup->xfer); platform_set_drvdata(pdev, qup); - ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq); - if (ret) { - dev_notice(qup->dev, "using default clock-frequency %d", - DEFAULT_CLK_FREQ); + if (scl_freq) { + dev_notice(qup->dev, "Using override frequency of %u\n", scl_freq); + clk_freq = scl_freq; + } else { + ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq); + if (ret) { + dev_notice(qup->dev, "using default clock-frequency %d", + DEFAULT_CLK_FREQ); + } } if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) { -- cgit v1.2.3