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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 <austinwc@codeaurora.org>
Reviewed-by: Sricharan R <sricharan@codeaurora.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Austin Christ 2018-05-10 10:13:57 -06:00 committed by Wolfram Sang
parent 71fbafcc45
commit d9f52281bc
1 changed files with 13 additions and 4 deletions
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17
drivers/i2c/busses/i2c-qup.c
View File

@ -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")) {