On 13.05.24 at 20:51:25 MESZ, Guenter Roeck wrote
> On 5/13/24 09:23, Marius Zachmann wrote:
> > Add support for reporting firmware and bootloader version using debugfs.
> > Update documentation accordingly.
> >
> > Signed-off-by: Marius Zachmann <mail@xxxxxxxxxxxxxxxxx>
> > ---
> > Changes in v3:
> > - use different debugfs directory name for each device
> >
> > Changes in v2:
> > - better patch description
> > - Documentation uses "Firmware version" and "Bootloader version"
> > - removed conditional CONFIG_DEBUG_FS
> > - get_fw_version gets called from ccp_debugfs_init
> > - get_fw_version does print a hid_notice when an error occurs
> > instead of failing.
> > ---
> > Documentation/hwmon/corsair-cpro.rst | 8 ++++
> > drivers/hwmon/corsair-cpro.c | 71 ++++++++++++++++++++++++++++
> > 2 files changed, 79 insertions(+)
> >
> > diff --git a/Documentation/hwmon/corsair-cpro.rst b/Documentation/hwmon/corsair-cpro.rst
> > index 751f95476b57..15077203a2f8 100644
> > --- a/Documentation/hwmon/corsair-cpro.rst
> > +++ b/Documentation/hwmon/corsair-cpro.rst
> > @@ -39,3 +39,11 @@ fan[1-6]_target Sets fan speed target rpm.
> > pwm[1-6] Sets the fan speed. Values from 0-255. Can only be read if pwm
> > was set directly.
> > ======================= =====================================================================
> > +
> > +Debugfs entries
> > +---------------
> > +
> > +======================= ===================
> > +firmware_version Firmware version
> > +bootloader_version Bootloader version
> > +======================= ===================
> > diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c
> > index 3e63666a61bd..f7d321d8676e 100644
> > --- a/drivers/hwmon/corsair-cpro.c
> > +++ b/drivers/hwmon/corsair-cpro.c
> > @@ -10,11 +10,13 @@
> >
> > #include <linux/bitops.h>
> > #include <linux/completion.h>
> > +#include <linux/debugfs.h>
> > #include <linux/hid.h>
> > #include <linux/hwmon.h>
> > #include <linux/kernel.h>
> > #include <linux/module.h>
> > #include <linux/mutex.h>
> > +#include <linux/seq_file.h>
> > #include <linux/slab.h>
> > #include <linux/spinlock.h>
> > #include <linux/types.h>
> > @@ -28,6 +30,8 @@
> > #define LABEL_LENGTH 11
> > #define REQ_TIMEOUT 300
> >
> > +#define CTL_GET_FW_VER 0x02 /* returns the firmware version in bytes 1-3 */
> > +#define CTL_GET_BL_VER 0x06 /* returns the bootloader version in bytes 1-2 */
> > #define CTL_GET_TMP_CNCT 0x10 /*
> > * returns in bytes 1-4 for each temp sensor:
> > * 0 not connected
> > @@ -78,6 +82,7 @@
> > struct ccp_device {
> > struct hid_device *hdev;
> > struct device *hwmon_dev;
> > + struct dentry *debugfs;
> > /* For reinitializing the completion below */
> > spinlock_t wait_input_report_lock;
> > struct completion wait_input_report;
> > @@ -88,6 +93,8 @@ struct ccp_device {
> > DECLARE_BITMAP(temp_cnct, NUM_TEMP_SENSORS);
> > DECLARE_BITMAP(fan_cnct, NUM_FANS);
> > char fan_label[6][LABEL_LENGTH];
> > + u8 firmware_ver[3];
> > + u8 bootloader_ver[2];
> > };
> >
> > /* converts response error in buffer to errno */
> > @@ -496,6 +503,66 @@ static int get_temp_cnct(struct ccp_device *ccp)
> > return 0;
> > }
> >
> > +/* read firmware and bootloader version */
> > +static void get_fw_version(struct ccp_device *ccp)
> > +{
> > + int ret;
> > +
> > + ret = send_usb_cmd(ccp, CTL_GET_FW_VER, 0, 0, 0);
> > + if (ret) {
> > + hid_notice(ccp->hdev, "Failed to read firmware version.\n");
>
> If this happens, the debugfs file should not be created, or at the very least
> display something like "unavailable".
>
> > + } else {
> > + ccp->firmware_ver[0] = ccp->buffer[1];
> > + ccp->firmware_ver[1] = ccp->buffer[2];
> > + ccp->firmware_ver[2] = ccp->buffer[3];
>
> That makes me wonder: What is in buffer[0] ?
buffer[0] is an errorcode returned by the device. It is read by ccp_get_errno,
which is called by send_usb_cmd.
>
> > + }
> > +
> > + ret = send_usb_cmd(ccp, CTL_GET_BL_VER, 0, 0, 0);
> > + if (ret) {
> > + hid_notice(ccp->hdev, "Failed to read bootloader version.\n");
>
> Same here.
>
> > + } else {
> > + ccp->bootloader_ver[0] = ccp->buffer[1];
> > + ccp->bootloader_ver[1] = ccp->buffer[2];
> > + }
> > +}
> > +
> > +static int firmware_show(struct seq_file *seqf, void *unused)
> > +{
> > + struct ccp_device *ccp = seqf->private;
> > +
> > + seq_printf(seqf, "%d.%d.%d\n",
> > + ccp->firmware_ver[0],
> > + ccp->firmware_ver[1],
> > + ccp->firmware_ver[2]);
> > +
> > + return 0;
> > +}
> > +DEFINE_SHOW_ATTRIBUTE(firmware);
> > +
> > +static int bootloader_show(struct seq_file *seqf, void *unused)
> > +{
> > + struct ccp_device *ccp = seqf->private;
> > +
> > + seq_printf(seqf, "%d.%d\n",
> > + ccp->bootloader_ver[0],
> > + ccp->bootloader_ver[1]);
> > +
> > + return 0;
> > +}
> > +DEFINE_SHOW_ATTRIBUTE(bootloader);
> > +
> > +static void ccp_debugfs_init(struct ccp_device *ccp)
> > +{
> > + char name[32];
> > +
> > + get_fw_version(ccp);
> > +
> > + scnprintf(name, sizeof(name), "corsaircpro-%s", dev_name(&ccp->hdev->dev));
> > + ccp->debugfs = debugfs_create_dir(name, NULL);
> > + debugfs_create_file("firmware_version", 0444, ccp->debugfs, ccp, &firmware_fops);
> > + debugfs_create_file("bootloader_version", 0444, ccp->debugfs, ccp, &bootloader_fops);
> > +}
> > +
> > static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
> > {
> > struct ccp_device *ccp;
> > @@ -542,6 +609,9 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id)
> > ret = get_fan_cnct(ccp);
> > if (ret)
> > goto out_hw_close;
> > +
> > + ccp_debugfs_init(ccp);
> > +
> > ccp->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, "corsaircpro",
> > ccp, &ccp_chip_info, NULL);
> > if (IS_ERR(ccp->hwmon_dev)) {
> > @@ -562,6 +632,7 @@ static void ccp_remove(struct hid_device *hdev)
> > {
> > struct ccp_device *ccp = hid_get_drvdata(hdev);
> >
> > + debugfs_remove_recursive(ccp->debugfs);
> > hwmon_device_unregister(ccp->hwmon_dev);
> > hid_hw_close(hdev);
> > hid_hw_stop(hdev);
>
>
