On 04/21/2017 03:15 PM, Takashi Iwai wrote:
The bytcr-rt5640 driver has a few quirk setups depending on the board, where the quirk value is set by DMI matching. When you have a new device to add the support, you often experience to try the different quirk by trial-and-error. Or, you may have a development model that still has no proper DMI string. In either case, you'd need to compile the driver at each time.
This patch introduces a module option to override the quirk value on the fly. User can boot like snd-soc-sst-bytcr-rt5640.quirk=0x4004 to override the default value without recompilation. It's a raw value, so user needs to check the source code for the meaning of each bit.
I am doing similar things at the moment, I folded IN1 and IN3 quirks together and was about to add a control to force single-ended/differential mics. The use of a parameter is not bad, we could stick it in a modprobe file and avoid writing more code.
That said, unless I am missing something, the problem with this parameter is that it will be overwritten by DMI quirks or the settings detected by the driver, see e.g. this code.
/* change defaults for Baytrail-CR capture */ byt_rt5640_quirk |= BYT_RT5640_IN1_MAP; byt_rt5640_quirk |= BYT_RT5640_DIFF_MIC; } else { byt_rt5640_quirk |= (BYT_RT5640_DMIC1_MAP | BYT_RT5640_DMIC_EN); }
/* check quirks before creating card */ dmi_check_system(byt_rt5640_quirk_table); log_quirks(&pdev->dev);
We may need a second variable to force the .quirk parameter to be used as is and avoid applying changes done at run-time.
Signed-off-by: Takashi Iwai tiwai@suse.de
sound/soc/intel/boards/bytcr_rt5640.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/sound/soc/intel/boards/bytcr_rt5640.c b/sound/soc/intel/boards/bytcr_rt5640.c index 5c7219fb3aa8..b848cbf575a1 100644 --- a/sound/soc/intel/boards/bytcr_rt5640.c +++ b/sound/soc/intel/boards/bytcr_rt5640.c @@ -19,6 +19,7 @@
#include <linux/init.h> #include <linux/module.h> +#include <linux/moduleparam.h> #include <linux/platform_device.h> #include <linux/acpi.h> #include <linux/device.h> @@ -57,7 +58,9 @@ struct byt_rt5640_private { struct clk *mclk; };
-static unsigned long byt_rt5640_quirk = BYT_RT5640_MCLK_EN; +static unsigned int byt_rt5640_quirk = BYT_RT5640_MCLK_EN; +module_param_named(quirk, byt_rt5640_quirk, int, 0444); +MODULE_PARM_DESC(quirk, "Board-specific quirk override");
static void log_quirks(struct device *dev) {