1 files changed, 24 insertions, 6 deletions

diff --git a/drivers/media/dvb/frontends/tda1004x.c b/drivers/media/dvb/frontends/tda1004x.c
index 1465ff77b0cb..4981cef8b444 100644
--- a/drivers/media/dvb/frontends/tda1004x.c
+++ b/drivers/media/dvb/frontends/tda1004x.c
@@ -162,7 +162,7 @@ static int tda1004x_read_byte(struct tda1004x_state *state, int reg)
         if (ret != 2) {
                 dprintk("%s: error reg=0x%x, ret=%i\n", __func__, reg,
                         ret);
-                return -1;
+                return -EINVAL;
         }
 
         dprintk("%s: success reg=0x%x, data=0x%x, ret=%i\n", __func__,
@@ -481,16 +481,18 @@ static void tda10046_init_plls(struct dvb_frontend* fe)
 static int tda10046_fwupload(struct dvb_frontend* fe)
 {
         struct tda1004x_state* state = fe->demodulator_priv;
-        int ret;
+        int ret, confc4;
         const struct firmware *fw;
 
         /* reset + wake up chip */
         if (state->config->xtal_freq == TDA10046_XTAL_4M) {
-                tda1004x_write_byteI(state, TDA1004X_CONFC4, 0);
+                confc4 = 0;
         } else {
                 dprintk("%s: 16MHz Xtal, reducing I2C speed\n", __func__);
-                tda1004x_write_byteI(state, TDA1004X_CONFC4, 0x80);
+                confc4 = 0x80;
         }
+        tda1004x_write_byteI(state, TDA1004X_CONFC4, confc4);
+
         tda1004x_write_mask(state, TDA10046H_CONF_TRISTATE1, 1, 0);
         /* set GPIO 1 and 3 */
         if (state->config->gpio_config != TDA10046_GPTRI) {
@@ -508,13 +510,29 @@ static int tda10046_fwupload(struct dvb_frontend* fe)
         if (tda1004x_check_upload_ok(state) == 0)
                 return 0;
 
+        /*
+           For i2c normal work, we need to slow down the bus speed.
+           However, the slow down breaks the eeprom firmware load.
+           So, use normal speed for eeprom booting and then restore the
+           i2c speed after that. Tested with MSI TV @nyware A/D board,
+           that comes with firmware version 29 inside their eeprom.
+
+           It should also be noticed that no other I2C transfer should
+           be in course while booting from eeprom, otherwise, tda10046
+           goes into an instable state. So, proper locking are needed
+           at the i2c bus master.
+         */
         printk(KERN_INFO "tda1004x: trying to boot from eeprom\n");
-        tda1004x_write_mask(state, TDA1004X_CONFC4, 4, 4);
+        tda1004x_write_byteI(state, TDA1004X_CONFC4, 4);
         msleep(300);
-        /* don't re-upload unless necessary */
+        tda1004x_write_byteI(state, TDA1004X_CONFC4, confc4);
+
+        /* Checks if eeprom firmware went without troubles */
         if (tda1004x_check_upload_ok(state) == 0)
                 return 0;
 
+        /* eeprom firmware didn't work. Load one manually. */
+
         if (state->config->request_firmware != NULL) {
                 /* request the firmware, this will block until someone uploads it */
                 printk(KERN_INFO "tda1004x: waiting for firmware upload...\n");