diff options
| -rw-r--r-- | drivers/hid/hid-cp2112.c | 74 |
1 files changed, 55 insertions, 19 deletions
diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c index 75398cb84fde..1d24a65b4295 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -156,6 +156,7 @@ struct cp2112_device { wait_queue_head_t wait; u8 read_data[61]; u8 read_length; + u8 hwversion; int xfer_status; atomic_t read_avail; atomic_t xfer_avail; @@ -446,6 +447,24 @@ static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data, return data_length + 3; } +static int cp2112_i2c_write_read_req(void *buf, u8 slave_address, + u8 *addr, int addr_length, + int read_length) +{ + struct cp2112_write_read_req_report *report = buf; + + if (read_length < 1 || read_length > 512 || + addr_length > sizeof(report->target_address)) + return -EINVAL; + + report->report = CP2112_DATA_WRITE_READ_REQUEST; + report->slave_address = slave_address << 1; + report->length = cpu_to_be16(read_length); + report->target_address_length = addr_length; + memcpy(report->target_address, addr, addr_length); + return addr_length + 5; +} + static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { @@ -453,26 +472,46 @@ static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, struct hid_device *hdev = dev->hdev; u8 buf[64]; ssize_t count; + ssize_t read_length = 0; + u8 *read_buf = NULL; unsigned int retries; int ret; hid_dbg(hdev, "I2C %d messages\n", num); - if (num != 1) { + if (num == 1) { + if (msgs->flags & I2C_M_RD) { + hid_dbg(hdev, "I2C read %#04x len %d\n", + msgs->addr, msgs->len); + read_length = msgs->len; + read_buf = msgs->buf; + count = cp2112_read_req(buf, msgs->addr, msgs->len); + } else { + hid_dbg(hdev, "I2C write %#04x len %d\n", + msgs->addr, msgs->len); + count = cp2112_i2c_write_req(buf, msgs->addr, + msgs->buf, msgs->len); + } + if (count < 0) + return count; + } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */ + num == 2 && + msgs[0].addr == msgs[1].addr && + !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) { + hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n", + msgs[0].addr, msgs[0].len, msgs[1].len); + read_length = msgs[1].len; + read_buf = msgs[1].buf; + count = cp2112_i2c_write_read_req(buf, msgs[0].addr, + msgs[0].buf, msgs[0].len, msgs[1].len); + if (count < 0) + return count; + } else { hid_err(hdev, "Multi-message I2C transactions not supported\n"); return -EOPNOTSUPP; } - if (msgs->flags & I2C_M_RD) - count = cp2112_read_req(buf, msgs->addr, msgs->len); - else - count = cp2112_i2c_write_req(buf, msgs->addr, msgs->buf, - msgs->len); - - if (count < 0) - return count; - ret = hid_hw_power(hdev, PM_HINT_FULLON); if (ret < 0) { hid_err(hdev, "power management error: %d\n", ret); @@ -508,11 +547,8 @@ static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, goto power_normal; } - if (!(msgs->flags & I2C_M_RD)) - goto finish; - - for (count = 0; count < msgs->len;) { - ret = cp2112_read(dev, msgs->buf + count, msgs->len - count); + for (count = 0; count < read_length;) { + ret = cp2112_read(dev, read_buf + count, read_length - count); if (ret < 0) goto power_normal; if (ret == 0) { @@ -521,7 +557,7 @@ static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, goto power_normal; } count += ret; - if (count > msgs->len) { + if (count > read_length) { /* * The hardware returned too much data. * This is mostly harmless because cp2112_read() @@ -531,15 +567,14 @@ static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, * it shouldn't go unnoticed. */ hid_err(hdev, "long read: %d > %zd\n", - ret, msgs->len - count + ret); + ret, read_length - count + ret); ret = -EIO; goto power_normal; } } -finish: /* return the number of transferred messages */ - ret = 1; + ret = num; power_normal: hid_hw_power(hdev, PM_HINT_NORMAL); @@ -1047,6 +1082,7 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id) dev->adap.dev.parent = &hdev->dev; snprintf(dev->adap.name, sizeof(dev->adap.name), "CP2112 SMBus Bridge on hiddev%d", hdev->minor); + dev->hwversion = buf[2]; init_waitqueue_head(&dev->wait); hid_device_io_start(hdev); |