fsi/fsi-master-gpio: More error handling cleanup

Remove calls to the empty and useless fsi_master_gpio_error()
function, and report CRC errors as "FSI_ERR_NO_SLAVE" when
reading an all 1's response.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Joel Stanley <joel@jms.id.au>

diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
index 351c12f2ac55fd16884c1cd747d1e3c063891780..da556da628463385be6a6fc23c97d3fa62e5a50c 100644 (file)
--- a/drivers/fsi/fsi-master-gpio.c
+++ b/drivers/fsi/fsi-master-gpio.c
@@ -41,13 +41,6 @@
 #define        FSI_GPIO_RESP_BUSY      1       /* Slave busy */
 #define        FSI_GPIO_RESP_ERRA      2       /* Any (misc) Error */
 #define        FSI_GPIO_RESP_ERRC      3       /* Slave reports master CRC error */
-#define        FSI_GPIO_MTOE           4       /* Master time out error */
-#define        FSI_GPIO_CRC_INVAL      5       /* Master reports slave CRC error */
-
-/* Normal slave responses */
-#define        FSI_GPIO_RESP_BUSY      1
-#define        FSI_GPIO_RESP_ACK       0
-#define        FSI_GPIO_RESP_ACKD      4
 
 #define        FSI_GPIO_MAX_BUSY       200
 #define        FSI_GPIO_MTOE_COUNT     1000
@@ -359,15 +352,6 @@ static void build_term_command(struct fsi_gpio_msg *cmd, uint8_t slave_id)
        msg_push_crc(cmd);
 }
 
-/*
- * Store information on master errors so handler can detect and clean
- * up the bus
- */
-static void fsi_master_gpio_error(struct fsi_master_gpio *master, int error)
-{
-
-}
-
 /*
  * Note: callers rely specifically on this returning -EAGAIN for
  * a CRC error detected in the response. Use other error code
@@ -396,7 +380,6 @@ static int read_one_response(struct fsi_master_gpio *master,
        if (i == FSI_GPIO_MTOE_COUNT) {
                dev_dbg(master->dev,
                        "Master time out waiting for response\n");
-               fsi_master_gpio_error(master, FSI_GPIO_MTOE);
                spin_unlock_irqrestore(&master->bit_lock, flags);
                return -ETIMEDOUT;
        }
@@ -422,8 +405,11 @@ static int read_one_response(struct fsi_master_gpio *master,
        crc = crc4(0, 1, 1);
        crc = crc4(crc, msg.msg, msg.bits);
        if (crc) {
-               dev_dbg(master->dev, "ERR response CRC\n");
-               fsi_master_gpio_error(master, FSI_GPIO_CRC_INVAL);
+               /* Check if it's all 1's, that probably means the host is off */
+               if (((~msg.msg) & ((1ull << msg.bits) - 1)) == 0)
+                       return -ENODEV;
+               dev_dbg(master->dev, "ERR response CRC msg: 0x%016llx (%d bits)\n",
+                       msg.msg, msg.bits);
                return -EAGAIN;
        }
 
@@ -538,12 +524,10 @@ retry:
 
        case FSI_GPIO_RESP_ERRA:
                dev_dbg(master->dev, "ERRA received: 0x%x\n", (int)response.msg);
-               fsi_master_gpio_error(master, response.msg);
                rc = -EIO;
                break;
        case FSI_GPIO_RESP_ERRC:
                dev_dbg(master->dev, "ERRC received: 0x%x\n", (int)response.msg);
-               fsi_master_gpio_error(master, response.msg);
                trace_fsi_master_gpio_crc_cmd_error(master);
                rc = -EAGAIN;
                break;