1 files changed, 64 insertions, 44 deletions

diff --git a/drivers/media/radio/si4713/si4713.c b/drivers/media/radio/si4713/si4713.c
index 4f3308f91608..5d26b9ad014d 100644
--- a/drivers/media/radio/si4713/si4713.c
+++ b/drivers/media/radio/si4713/si4713.c
@@ -27,11 +27,11 @@
 #include <linux/i2c.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
-#include <linux/regulator/consumer.h>
 #include <linux/module.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-ioctl.h>
 #include <media/v4l2-common.h>
+#include <linux/regulator/consumer.h>
 
 #include "si4713.h"
 
@@ -213,6 +213,7 @@ static int si4713_send_command(struct si4713_device *sdev, const u8 command,
                                 u8 response[], const int respn, const int usecs)
 {
         struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
+        unsigned long until_jiffies;
         u8 data1[MAX_ARGS + 1];
         int err;
 
@@ -228,30 +229,39 @@ static int si4713_send_command(struct si4713_device *sdev, const u8 command,
         if (err != argn + 1) {
                 v4l2_err(&sdev->sd, "Error while sending command 0x%02x\n",
                         command);
-                return (err > 0) ? -EIO : err;
+                return err < 0 ? err : -EIO;
         }
 
+        until_jiffies = jiffies + usecs_to_jiffies(usecs) + 1;
+
         /* Wait response from interrupt */
-        if (!wait_for_completion_timeout(&sdev->work,
+        if (client->irq) {
+                if (!wait_for_completion_timeout(&sdev->work,
                                 usecs_to_jiffies(usecs) + 1))
-                v4l2_warn(&sdev->sd,
+                        v4l2_warn(&sdev->sd,
                                 "(%s) Device took too much time to answer.\n",
                                 __func__);
-
-        /* Then get the response */
-        err = i2c_master_recv(client, response, respn);
-        if (err != respn) {
-                v4l2_err(&sdev->sd,
-                        "Error while reading response for command 0x%02x\n",
-                        command);
-                return (err > 0) ? -EIO : err;
         }
 
-        DBG_BUFFER(&sdev->sd, "Response", response, respn);
-        if (check_command_failed(response[0]))
-                return -EBUSY;
+        do {
+                err = i2c_master_recv(client, response, respn);
+                if (err != respn) {
+                        v4l2_err(&sdev->sd,
+                                "Error %d while reading response for command 0x%02x\n",
+                                err, command);
+                        return err < 0 ? err : -EIO;
+                }
+
+                DBG_BUFFER(&sdev->sd, "Response", response, respn);
+                if (!check_command_failed(response[0]))
+                        return 0;
 
-        return 0;
+                if (client->irq)
+                        return -EBUSY;
+                msleep(1);
+        } while (jiffies <= until_jiffies);
+
+        return -EBUSY;
 }
 
 /*
@@ -344,14 +354,15 @@ static int si4713_write_property(struct si4713_device *sdev, u16 prop, u16 val)
  */
 static int si4713_powerup(struct si4713_device *sdev)
 {
+        struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
         int err;
         u8 resp[SI4713_PWUP_NRESP];
         /*
          *      .First byte = Enabled interrupts and boot function
          *      .Second byte = Input operation mode
          */
-        const u8 args[SI4713_PWUP_NARGS] = {
-                SI4713_PWUP_CTSIEN | SI4713_PWUP_GPO2OEN | SI4713_PWUP_FUNC_TX,
+        u8 args[SI4713_PWUP_NARGS] = {
+                SI4713_PWUP_GPO2OEN | SI4713_PWUP_FUNC_TX,
                 SI4713_PWUP_OPMOD_ANALOG,
         };
 
@@ -369,6 +380,9 @@ static int si4713_powerup(struct si4713_device *sdev)
                 gpio_set_value(sdev->gpio_reset, 1);
         }
 
+        if (client->irq)
+                args[0] |= SI4713_PWUP_CTSIEN;
+
         err = si4713_send_command(sdev, SI4713_CMD_POWER_UP,
                                         args, ARRAY_SIZE(args),
                                         resp, ARRAY_SIZE(resp),
@@ -380,7 +394,8 @@ static int si4713_powerup(struct si4713_device *sdev)
                 v4l2_dbg(1, debug, &sdev->sd, "Device in power up mode\n");
                 sdev->power_state = POWER_ON;
 
-                err = si4713_write_property(sdev, SI4713_GPO_IEN,
+                if (client->irq)
+                        err = si4713_write_property(sdev, SI4713_GPO_IEN,
                                                 SI4713_STC_INT | SI4713_CTS);
         } else {
                 if (gpio_is_valid(sdev->gpio_reset))
@@ -465,33 +480,39 @@ static int si4713_checkrev(struct si4713_device *sdev)
  */
 static int si4713_wait_stc(struct si4713_device *sdev, const int usecs)
 {
-        int err;
+        struct i2c_client *client = v4l2_get_subdevdata(&sdev->sd);
         u8 resp[SI4713_GET_STATUS_NRESP];
+        unsigned long start_jiffies = jiffies;
+        int err;
 
-        /* Wait response from STC interrupt */
-        if (!wait_for_completion_timeout(&sdev->work,
-                        usecs_to_jiffies(usecs) + 1))
+        if (client->irq &&
+            !wait_for_completion_timeout(&sdev->work, usecs_to_jiffies(usecs) + 1))
                 v4l2_warn(&sdev->sd,
-                        "%s: device took too much time to answer (%d usec).\n",
-                                __func__, usecs);
-
-        /* Clear status bits */
-        err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
-                                        NULL, 0,
-                                        resp, ARRAY_SIZE(resp),
-                                        DEFAULT_TIMEOUT);
-
-        if (err < 0)
-                goto exit;
-
-        v4l2_dbg(1, debug, &sdev->sd,
-                        "%s: status bits: 0x%02x\n", __func__, resp[0]);
-
-        if (!(resp[0] & SI4713_STC_INT))
-                err = -EIO;
-
-exit:
-        return err;
+                        "(%s) Device took too much time to answer.\n", __func__);
+
+        for (;;) {
+                /* Clear status bits */
+                err = si4713_send_command(sdev, SI4713_CMD_GET_INT_STATUS,
+                                NULL, 0,
+                                resp, ARRAY_SIZE(resp),
+                                DEFAULT_TIMEOUT);
+                /* The USB device returns errors when it waits for the
+                 * STC bit to be set. Hence polling */
+                if (err >= 0) {
+                        v4l2_dbg(1, debug, &sdev->sd,
+                                "%s: status bits: 0x%02x\n", __func__, resp[0]);
+
+                        if (resp[0] & SI4713_STC_INT)
+                                return 0;
+                }
+                if (jiffies_to_usecs(jiffies - start_jiffies) > usecs)
+                        return err < 0 ? err : -EIO;
+                /* We sleep here for 3 ms in order to avoid flooding the device
+                 * with USB requests. The si4713 USB driver was developed
+                 * by reverse engineering the Windows USB driver. The windows
+                 * driver also has a ~2.5 ms delay between responses. */
+                msleep(3);
+        }
 }
 
 /*
@@ -1024,7 +1045,6 @@ static int si4713_initialize(struct si4713_device *sdev)
         if (rval < 0)
                 return rval;
 
-
         sdev->frequency = DEFAULT_FREQUENCY;
         sdev->stereo = 1;
         sdev->tune_rnl = DEFAULT_TUNE_RNL;