From 27602842060484b564cd725241b402b0bddfb830 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Sat, 3 Nov 2012 17:47:58 +0800 Subject: [PATCH] firmware loader: introduce module parameter to customize(v4) fw search path This patch introduces one module parameter of 'path' in firmware_class to support customizing firmware image search path, so that people can use its own firmware path if the default built-in paths can't meet their demand[1], and the typical usage is passing the below from kernel command parameter when 'firmware_class' is built in kernel: firmware_class.path=$CUSTOMIZED_PATH [1], https://lkml.org/lkml/2012/10/11/337 Cc: Linus Torvalds Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- Documentation/firmware_class/README | 5 +++++ drivers/base/firmware_class.c | 17 ++++++++++++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/Documentation/firmware_class/README b/Documentation/firmware_class/README index 815b711bcd85..e9fce78c4137 100644 --- a/Documentation/firmware_class/README +++ b/Documentation/firmware_class/README @@ -22,12 +22,17 @@ - calls request_firmware(&fw_entry, $FIRMWARE, device) - kernel searchs the fimware image with name $FIRMWARE directly in the below search path of root filesystem: + User customized search path by module parameter 'path'[1] "/lib/firmware/updates/" UTS_RELEASE, "/lib/firmware/updates", "/lib/firmware/" UTS_RELEASE, "/lib/firmware" - If found, goto 7), else goto 2) + [1], the 'path' is a string parameter which length should be less + than 256, user should pass 'firmware_class.path=$CUSTOMIZED_PATH' + if firmware_class is built in kernel(the general situation) + 2), userspace: - /sys/class/firmware/xxx/{loading,data} appear. - hotplug gets called with a firmware identifier in $FIRMWARE diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 4b04ec4bd2f0..7888af7941a0 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -269,13 +269,23 @@ static void fw_free_buf(struct firmware_buf *buf) } /* direct firmware loading support */ -static const char *fw_path[] = { +static char fw_path_para[256]; +static const char * const fw_path[] = { + fw_path_para, "/lib/firmware/updates/" UTS_RELEASE, "/lib/firmware/updates", "/lib/firmware/" UTS_RELEASE, "/lib/firmware" }; +/* + * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH' + * from kernel command line because firmware_class is generally built in + * kernel instead of module. + */ +module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644); +MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path"); + /* Don't inline this: 'struct kstat' is biggish */ static noinline_for_stack long fw_file_size(struct file *file) { @@ -317,6 +327,11 @@ static bool fw_get_filesystem_firmware(struct firmware_buf *buf) for (i = 0; i < ARRAY_SIZE(fw_path); i++) { struct file *file; + + /* skip the unset customized path */ + if (!fw_path[i][0]) + continue; + snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id); file = filp_open(path, O_RDONLY, 0);