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authorAustin Christ <austinwc@codeaurora.org>2018-05-10 10:13:57 -0600
committerWolfram Sang <wsa@the-dreams.de>2018-05-29 19:58:50 +0200
commitd9f52281bc09bd49374486f5e21fad7b8d3a5b3c (patch)
treea5af9722d6794248a5c5ce6d22d55806a3a63f86 /drivers/i2c
parent71fbafcc45fed7c647987495900b8f6ff29fc5aa (diff)
downloadlinux-d9f52281bc09bd49374486f5e21fad7b8d3a5b3c.tar.bz2
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>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-qup.c17
1 files changed, 13 insertions, 4 deletions
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")) {