diff options
Diffstat (limited to 'drivers/hid/hid-mcp2221.c')
| -rw-r--r-- | drivers/hid/hid-mcp2221.c | 32 |
1 files changed, 23 insertions, 9 deletions
diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c index ecd830ce0acf..b242a312c377 100644 --- a/drivers/hid/hid-mcp2221.c +++ b/drivers/hid/hid-mcp2221.c @@ -49,6 +49,7 @@ enum { MCP2221_I2C_MASK_ADDR_NACK = 0x40, MCP2221_I2C_WRADDRL_SEND = 0x21, MCP2221_I2C_ADDR_NACK = 0x25, + MCP2221_I2C_READ_PARTIAL = 0x54, MCP2221_I2C_READ_COMPL = 0x55, MCP2221_ALT_F_NOT_GPIOV = 0xEE, MCP2221_ALT_F_NOT_GPIOD = 0xEF, @@ -297,6 +298,7 @@ static int mcp_i2c_smbus_read(struct mcp2221 *mcp, { int ret; u16 total_len; + int retries = 0; mcp->txbuf[0] = type; if (msg) { @@ -320,20 +322,31 @@ static int mcp_i2c_smbus_read(struct mcp2221 *mcp, mcp->rxbuf_idx = 0; do { + /* Wait for the data to be read by the device */ + usleep_range(980, 1000); + memset(mcp->txbuf, 0, 4); mcp->txbuf[0] = MCP2221_I2C_GET_DATA; ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1); - if (ret) - return ret; - - ret = mcp_chk_last_cmd_status_free_bus(mcp); - if (ret) - return ret; - - usleep_range(980, 1000); + if (ret) { + if (retries < 5) { + /* The data wasn't ready to read. + * Wait a bit longer and try again. + */ + usleep_range(90, 100); + retries++; + } else { + return ret; + } + } else { + retries = 0; + } } while (mcp->rxbuf_idx < total_len); + usleep_range(980, 1000); + ret = mcp_chk_last_cmd_status_free_bus(mcp); + return ret; } @@ -799,7 +812,8 @@ static int mcp2221_raw_event(struct hid_device *hdev, mcp->status = -EIO; break; } - if (data[2] == MCP2221_I2C_READ_COMPL) { + if (data[2] == MCP2221_I2C_READ_COMPL || + data[2] == MCP2221_I2C_READ_PARTIAL) { buf = mcp->rxbuf; memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]); mcp->rxbuf_idx = mcp->rxbuf_idx + data[3]; |