[PATCH] dvb: flexcop: i2c read fixes

rewrote the i2c-reading-part (no more ack-error ignoring, which was inherited
from the skystar2-driver)

Signed-off-by: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 63 insertions, 60 deletions

diff --git a/drivers/media/dvb/b2c2/flexcop-i2c.c b/drivers/media/dvb/b2c2/flexcop-i2c.c
index 736251f393c2..be4266d4ae91 100644
--- a/drivers/media/dvb/b2c2/flexcop-i2c.c
+++ b/drivers/media/dvb/b2c2/flexcop-i2c.c
@@ -9,9 +9,9 @@
 
 #define FC_MAX_I2C_RETRIES 100000
 
-static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r100, int max_ack_errors)
+static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r100)
 {
-        int i,ack_errors = 0;
+        int i;
         flexcop_ibi_value r;
 
         r100->tw_sm_c_100.working_start = 1;
@@ -31,11 +31,7 @@ static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r
                         }
                 } else {
                         deb_i2c("suffering from an i2c ack_error\n");
-                        if (++ack_errors >= max_ack_errors)
-                                break;
-
-                        fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
-                        fc->write_ibi_reg(fc, tw_sm_c_100, *r100);
+                        return -EREMOTEIO;
                 }
         }
         deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n",i);
@@ -48,19 +44,30 @@ static int flexcop_i2c_read4(struct flexcop_device *fc, flexcop_ibi_value r100,
         int len = r100.tw_sm_c_100.total_bytes, /* remember total_bytes is buflen-1 */
                 ret;
 
-        if ((ret = flexcop_i2c_operation(fc,&r100,30)) != 0)
-                return ret;
-
-        r104 = fc->read_ibi_reg(fc,tw_sm_c_104);
-
-        deb_i2c("read: r100: %08x, r104: %08x\n",r100.raw,r104.raw);
+        if ((ret = flexcop_i2c_operation(fc,&r100)) != 0) {
+                /* The Cablestar needs a different kind of i2c-transfer (does not
+                 * support "Repeat Start"):
+                 * wait for the ACK failure,
+                 * and do a subsequent read with the Bit 30 enabled
+                 */
+                r100.tw_sm_c_100.no_base_addr_ack_error = 1;
+                if ((ret = flexcop_i2c_operation(fc,&r100)) != 0) {
+                        deb_i2c("no_base_addr read failed. %d\n",ret);
+                        return ret;
+                }
+        }
 
-        /* there is at least one byte, otherwise we wouldn't be here */
         buf[0] = r100.tw_sm_c_100.data1_reg;
 
-        if (len > 0) buf[1] = r104.tw_sm_c_104.data2_reg;
-        if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
-        if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
+        if (len > 0) {
+                r104 = fc->read_ibi_reg(fc,tw_sm_c_104);
+                deb_i2c("read: r100: %08x, r104: %08x\n",r100.raw,r104.raw);
+
+                /* there is at least one more byte, otherwise we wouldn't be here */
+                buf[1] = r104.tw_sm_c_104.data2_reg;
+                if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
+                if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
+        }
 
         return 0;
 }
@@ -82,9 +89,45 @@ static int flexcop_i2c_write4(struct flexcop_device *fc, flexcop_ibi_value r100,
 
         /* write the additional i2c data before doing the actual i2c operation */
         fc->write_ibi_reg(fc,tw_sm_c_104,r104);
+        return flexcop_i2c_operation(fc,&r100);
+}
+
+int flexcop_i2c_request(struct flexcop_device *fc, flexcop_access_op_t op,
+                flexcop_i2c_port_t port, u8 chipaddr, u8 addr, u8 *buf, u16 len)
+{
+        int ret;
+        u16 bytes_to_transfer;
+        flexcop_ibi_value r100;
+
+        deb_i2c("op = %d\n",op);
+        r100.raw = 0;
+        r100.tw_sm_c_100.chipaddr = chipaddr;
+        r100.tw_sm_c_100.twoWS_rw = op;
+        r100.tw_sm_c_100.twoWS_port_reg = port;
+
+        while (len != 0) {
+                bytes_to_transfer = len > 4 ? 4 : len;
 
-        return flexcop_i2c_operation(fc,&r100,30);
+                r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
+                r100.tw_sm_c_100.baseaddr = addr;
+
+                if (op == FC_READ)
+                        ret = flexcop_i2c_read4(fc, r100, buf);
+                else
+                        ret = flexcop_i2c_write4(fc,r100, buf);
+
+                if (ret < 0)
+                        return ret;
+
+                buf  += bytes_to_transfer;
+                addr += bytes_to_transfer;
+                len  -= bytes_to_transfer;
+        };
+
+        return 0;
 }
+/* exported for PCI i2c */
+EXPORT_SYMBOL(flexcop_i2c_request);
 
 /* master xfer callback for demodulator */
 static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
@@ -123,43 +166,6 @@ static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs
         return ret;
 }
 
-int flexcop_i2c_request(struct flexcop_device *fc, flexcop_access_op_t op,
-                flexcop_i2c_port_t port, u8 chipaddr, u8 addr, u8 *buf, u16 len)
-{
-        int ret;
-        u16 bytes_to_transfer;
-        flexcop_ibi_value r100;
-
-        deb_i2c("op = %d\n",op);
-        r100.raw = 0;
-        r100.tw_sm_c_100.chipaddr = chipaddr;
-        r100.tw_sm_c_100.twoWS_rw = op;
-        r100.tw_sm_c_100.twoWS_port_reg = port;
-
-        while (len != 0) {
-                bytes_to_transfer = len > 4 ? 4 : len;
-
-                r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
-                r100.tw_sm_c_100.baseaddr = addr;
-
-                if (op == FC_READ)
-                        ret = flexcop_i2c_read4(fc, r100, buf);
-                else
-                        ret = flexcop_i2c_write4(fc,r100, buf);
-
-                if (ret < 0)
-                        return ret;
-
-                buf  += bytes_to_transfer;
-                addr += bytes_to_transfer;
-                len  -= bytes_to_transfer;
-        };
-
-        return 0;
-}
-/* exported for PCI i2c */
-EXPORT_SYMBOL(flexcop_i2c_request);
-
 static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
 {
         return I2C_FUNC_I2C;
diff --git a/drivers/media/dvb/b2c2/flexcop-reg.h b/drivers/media/dvb/b2c2/flexcop-reg.h
index 41835c5280ae..5e131be55cb3 100644
--- a/drivers/media/dvb/b2c2/flexcop-reg.h
+++ b/drivers/media/dvb/b2c2/flexcop-reg.h
@@ -692,9 +692,10 @@ typedef enum {
         wan_ctrl_reg_71c    = 0x71c,
 } flexcop_ibi_register;
 
-#define flexcop_set_ibi_value(reg,attr,val) \
+#define flexcop_set_ibi_value(reg,attr,val) { \
         flexcop_ibi_value v = fc->read_ibi_reg(fc,reg); \
         v.reg.attr = val; \
         fc->write_ibi_reg(fc,reg,v); \
+}
 
 #endif
diff --git a/drivers/media/dvb/b2c2/flexcop.c b/drivers/media/dvb/b2c2/flexcop.c
index df55e4c8ecd8..8b5d14dd36e3 100644
--- a/drivers/media/dvb/b2c2/flexcop.c
+++ b/drivers/media/dvb/b2c2/flexcop.c
@@ -184,10 +184,6 @@ static void flexcop_reset(struct flexcop_device *fc)
         fc->write_ibi_reg(fc,misc_204,v204);
         v204.misc_204.Per_reset_sig = 1;
         fc->write_ibi_reg(fc,misc_204,v204);
-
-/*      v208.raw = 0;
-        v208.ctrl_208.Null_filter_sig = 1;
-        fc->write_ibi_reg(fc,ctrl_208,v208);*/
 }
 
 struct flexcop_device *flexcop_device_kmalloc(size_t bus_specific_len)