diff options
Diffstat (limited to 'drivers/hid/i2c-hid/i2c-hid.c')
-rw-r--r-- | drivers/hid/i2c-hid/i2c-hid.c | 69 |
1 files changed, 68 insertions, 1 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c index b3ec4f2de875..865e7c262322 100644 --- a/drivers/hid/i2c-hid/i2c-hid.c +++ b/drivers/hid/i2c-hid/i2c-hid.c @@ -41,6 +41,11 @@ #include <linux/i2c/i2c-hid.h> +#include "../hid-ids.h" + +/* quirks to control the device */ +#define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV BIT(0) + /* flags */ #define I2C_HID_STARTED 0 #define I2C_HID_RESET_PENDING 1 @@ -143,6 +148,7 @@ struct i2c_hid { char *argsbuf; /* Command arguments buffer */ unsigned long flags; /* device flags */ + unsigned long quirks; /* Various quirks */ wait_queue_head_t wait; /* For waiting the interrupt */ struct gpio_desc *desc; @@ -154,6 +160,39 @@ struct i2c_hid { struct mutex reset_lock; }; +static const struct i2c_hid_quirks { + __u16 idVendor; + __u16 idProduct; + __u32 quirks; +} i2c_hid_quirks[] = { + { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8752, + I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV }, + { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755, + I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV }, + { 0, 0 } +}; + +/* + * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device + * @idVendor: the 16-bit vendor ID + * @idProduct: the 16-bit product ID + * + * Returns: a u32 quirks value. + */ +static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct) +{ + u32 quirks = 0; + int n; + + for (n = 0; i2c_hid_quirks[n].idVendor; n++) + if (i2c_hid_quirks[n].idVendor == idVendor && + (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID || + i2c_hid_quirks[n].idProduct == idProduct)) + quirks = i2c_hid_quirks[n].quirks; + + return quirks; +} + static int __i2c_hid_command(struct i2c_client *client, const struct i2c_hid_cmd *command, u8 reportID, u8 reportType, u8 *args, int args_len, @@ -346,11 +385,27 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state) i2c_hid_dbg(ihid, "%s\n", __func__); + /* + * Some devices require to send a command to wakeup before power on. + * The call will get a return value (EREMOTEIO) but device will be + * triggered and activated. After that, it goes like a normal device. + */ + if (power_state == I2C_HID_PWR_ON && + ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) { + ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0); + + /* Device was already activated */ + if (!ret) + goto set_pwr_exit; + } + ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state, 0, NULL, 0, NULL, 0); + if (ret) dev_err(&client->dev, "failed to change power setting.\n"); +set_pwr_exit: return ret; } @@ -372,6 +427,15 @@ static int i2c_hid_hwreset(struct i2c_client *client) if (ret) goto out_unlock; + /* + * The HID over I2C specification states that if a DEVICE needs time + * after the PWR_ON request, it should utilise CLOCK stretching. + * However, it has been observered that the Windows driver provides a + * 1ms sleep between the PWR_ON and RESET requests and that some devices + * rely on this. + */ + usleep_range(1000, 5000); + i2c_hid_dbg(ihid, "resetting...\n"); ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0); @@ -540,7 +604,8 @@ static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) { /* the worst case is computed from the set_report command with a * reportID > 15 and the maximum report length */ - int args_len = sizeof(__u8) + /* optional ReportID byte */ + int args_len = sizeof(__u8) + /* ReportID */ + sizeof(__u8) + /* optional ReportID byte */ sizeof(__u16) + /* data register */ sizeof(__u16) + /* size of the report */ report_size; /* report */ @@ -1050,6 +1115,8 @@ static int i2c_hid_probe(struct i2c_client *client, client->name, hid->vendor, hid->product); strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys)); + ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product); + ret = hid_add_device(hid); if (ret) { if (ret != -ENODEV) |