V4L/DVB (5423): M920x: i2c cleanups

- Implement m920x i2c as suggested by Pierre Willenbrock
- remove "magic" hack
- r/w bit is not part of the i2c address
- move hardware remarks to header file

Signed-off-by: Aapo Tahkola <aet@rasterburn.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

2 files changed, 51 insertions, 50 deletions

diff --git a/drivers/media/dvb/dvb-usb/m920x.c b/drivers/media/dvb/dvb-usb/m920x.c
index d48b24d9abf4..92f76c918c79 100644
--- a/drivers/media/dvb/dvb-usb/m920x.c
+++ b/drivers/media/dvb/dvb-usb/m920x.c
@@ -137,52 +137,45 @@ static int m9206_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[],
                           int num)
 {
         struct dvb_usb_device *d = i2c_get_adapdata(adap);
-        struct m9206_state *m = d->priv;
-        int i;
+        int i, j;
         int ret = 0;
 
         if (mutex_lock_interruptible(&d->i2c_mutex) < 0)
                 return -EAGAIN;
 
-        if (num > 2)
-                return -EINVAL;
-
         for (i = 0; i < num; i++) {
-                if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].addr, 0x80)) != 0)
-                        goto unlock;
-
-                if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].buf[0], 0x0)) != 0)
-                        goto unlock;
-
-                if (i + 1 < num && msg[i + 1].flags & I2C_M_RD) {
-                        int i2c_i;
-
-                        for (i2c_i = 0; i2c_i < M9206_I2C_MAX; i2c_i++)
-                                if (msg[i].addr == m->i2c_r[i2c_i].addr)
-                                        break;
+                if (msg[i].flags & I2C_M_RD) {
 
-                        if (i2c_i >= M9206_I2C_MAX) {
-                                deb_rc("No magic for i2c addr!\n");
-                                ret = -EINVAL;
+                        if ((ret = m9206_write(d->udev, M9206_I2C, (msg[i].addr << 1) | 0x01, 0x80)) != 0)
                                 goto unlock;
+
+                        for(j = 0; j < msg[i].len; j++) {
+                                if (j + 1 == msg[i].len && i + 1== num) {
+                                        if ((ret = m9206_read(d->udev, M9206_I2C, 0x0, 0x60, &msg[i].buf[j], msg[i].len)) != 0)
+                                                goto unlock;
+                                } else {
+                                        if ((ret = m9206_read(d->udev, M9206_I2C, 0x0, 0x21, &msg[i].buf[j], msg[i].len)) != 0)
+                                                goto unlock;
+                                }
                         }
 
-                        if ((ret = m9206_write(d->udev, M9206_I2C, m->i2c_r[i2c_i].magic, 0x80)) != 0)
+                } else {
+                        if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].addr << 1, 0x80)) != 0)
                                 goto unlock;
 
-                        if ((ret = m9206_read(d->udev, M9206_I2C, 0x0, 0x60, msg[i + 1].buf, msg[i + 1].len)) != 0)
-                                goto unlock;
+                        for(j = 0; j < msg[i].len; j++) {
+                                if (j + 1 == msg[i].len && i + 1== num) {
+                                        if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].buf[j], 0x40)) != 0)
+                                                goto unlock;
 
-                        i++;
-                } else {
-                        if (msg[i].len != 2)
-                                return -EINVAL;
-
-                        if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].buf[1], 0x40)) != 0)
-                                goto unlock;
+                                } else {
+                                        if ((ret = m9206_write(d->udev, M9206_I2C, msg[i].buf[j], 0x0)) != 0)
+                                                goto unlock;
+                                }
+                        }
                 }
         }
-        ret = i;
+        ret = num;
         unlock:
         mutex_unlock(&d->i2c_mutex);
 
@@ -381,20 +374,15 @@ static int megasky_mt352_demod_init(struct dvb_frontend *fe)
 }
 
 static struct mt352_config megasky_mt352_config = {
-        .demod_address = 0x1e,
+        .demod_address = 0x0f,
         .no_tuner = 1,
         .demod_init = megasky_mt352_demod_init,
 };
 
 static int megasky_mt352_frontend_attach(struct dvb_usb_adapter *adap)
 {
-        struct m9206_state *m = adap->dev->priv;
-
         deb_rc("megasky_frontend_attach!\n");
 
-        m->i2c_r[M9206_I2C_DEMOD].addr = megasky_mt352_config.demod_address;
-        m->i2c_r[M9206_I2C_DEMOD].magic = 0x1f;
-
         if ((adap->fe = dvb_attach(mt352_attach, &megasky_mt352_config, &adap->dev->i2c_adap)) == NULL)
                 return -EIO;
 
@@ -402,16 +390,11 @@ static int megasky_mt352_frontend_attach(struct dvb_usb_adapter *adap)
 }
 
 static struct qt1010_config megasky_qt1010_config = {
-        .i2c_address = 0xc4
+        .i2c_address = 0x62
 };
 
 static int megasky_qt1010_tuner_attach(struct dvb_usb_adapter *adap)
 {
-        struct m9206_state *m = adap->dev->priv;
-
-        m->i2c_r[M9206_I2C_TUNER].addr = megasky_qt1010_config.i2c_address;
-        m->i2c_r[M9206_I2C_TUNER].magic = 0xc5;
-
         if (dvb_attach(qt1010_attach, adap->fe, &adap->dev->i2c_adap,
                        &megasky_qt1010_config) == NULL)
                 return -ENODEV;
diff --git a/drivers/media/dvb/dvb-usb/m920x.h b/drivers/media/dvb/dvb-usb/m920x.h
index c354196ffe5d..c5ef592cbfee 100644
--- a/drivers/media/dvb/dvb-usb/m920x.h
+++ b/drivers/media/dvb/dvb-usb/m920x.h
@@ -19,17 +19,35 @@
 
 #define M9206_MAX_FILTERS 8
 
-#define M9206_I2C_TUNER 0
-#define M9206_I2C_DEMOD 1
-#define M9206_I2C_MAX   2
+/*
+sequences found in logs:
+[index value]
+0x80 write addr
+(0x00 out byte)*
+0x40 out byte
+
+0x80 write addr
+(0x00 out byte)*
+0x80 read addr
+(0x21 in byte)*
+0x60 in byte
+
+this sequence works:
+0x80 read addr
+(0x21 in byte)*
+0x60 in byte
+
+_my guess_:
+0x80: begin i2c transfer using address. value=address<<1|(reading?1:0)
+0x00: write byte
+0x21: read byte, more to follow
+0x40: write last byte of message sequence
+0x60: read last byte of message sequence
+ */
 
 struct m9206_state {
         u16 filters[M9206_MAX_FILTERS];
         int filtering_enabled;
         int rep_count;
-        struct {
-                unsigned char addr;
-                unsigned char magic;
-        }i2c_r[M9206_I2C_MAX];
 };
 #endif