[media] rtl28xx: reimplement I2C adapter

It is almost perfect now!

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/dvb/dvb-usb/rtl28xxu.c b/drivers/media/dvb/dvb-usb/rtl28xxu.c
index 8772fe8..a6b5c04 100644 (file)
--- a/drivers/media/dvb/dvb-usb/rtl28xxu.c
+++ b/drivers/media/dvb/dvb-usb/rtl28xxu.c
@@ -134,11 +134,29 @@ static int rtl28xxu_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[],
 {
        int ret;
        struct dvb_usb_device *d = i2c_get_adapdata(adap);
+       struct rtl28xxu_priv *priv = d->priv;
        struct rtl28xxu_req req;
 
        /*
         * It is not known which are real I2C bus xfer limits, but testing
         * with RTL2831U + MT2060 gives max RD 24 and max WR 22 bytes.
+        * TODO: find out RTL2832U lens
+        */
+
+       /*
+        * I2C adapter logic looks rather complicated due to fact it handles
+        * three different access methods. Those methods are;
+        * 1) integrated demod access
+        * 2) old I2C access
+        * 3) new I2C access
+        *
+        * Used method is selected in order 1, 2, 3. Method 3 can handle all
+        * requests but there is two reasons why not use it always;
+        * 1) It is most expensive, usually two USB messages are needed
+        * 2) At least RTL2831U does not support it
+        *
+        * Method 3 is needed in case of I2C write+read (typical register read)
+        * where write is more than one byte.
         */
 
        if (mutex_lock_interruptible(&d->i2c_mutex) < 0)
@@ -146,44 +164,73 @@ static int rtl28xxu_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[],
 
        if (num == 2 && !(msg[0].flags & I2C_M_RD) &&
                (msg[1].flags & I2C_M_RD)) {
-               if (msg[0].len > 2 || msg[1].len > 24) {
+               if (msg[0].len > 24 || msg[1].len > 24) {
+                       /* TODO: check msg[0].len max */
                        ret = -EOPNOTSUPP;
                        goto err_unlock;
-               }
-               if (msg[0].addr == 0x10) {
-                       /* integrated demod */
-                       req.value = (msg[0].buf[1] << 8) | (msg[0].addr << 1);
-                       req.index = CMD_DEMOD_RD | msg[0].buf[0];
+               } else if (msg[0].addr == 0x10) {
+                       /* method 1 - integrated demod */
+                       req.value = (msg[0].buf[0] << 8) | (msg[0].addr << 1);
+                       req.index = CMD_DEMOD_RD | priv->page;
                        req.size = msg[1].len;
                        req.data = &msg[1].buf[0];
                        ret = rtl28xxu_ctrl_msg(d, &req);
-               } else {
-                       /* real I2C */
+               } else if (msg[0].len < 2) {
+                       /* method 2 - old I2C */
                        req.value = (msg[0].buf[0] << 8) | (msg[0].addr << 1);
                        req.index = CMD_I2C_RD;
                        req.size = msg[1].len;
                        req.data = &msg[1].buf[0];
                        ret = rtl28xxu_ctrl_msg(d, &req);
+               } else {
+                       /* method 3 - new I2C */
+                       req.value = (msg[0].addr << 1);
+                       req.index = CMD_I2C_DA_WR;
+                       req.size = msg[0].len;
+                       req.data = msg[0].buf;
+                       ret = rtl28xxu_ctrl_msg(d, &req);
+                       if (ret)
+                               goto err_unlock;
+
+                       req.value = (msg[0].addr << 1);
+                       req.index = CMD_I2C_DA_RD;
+                       req.size = msg[1].len;
+                       req.data = msg[1].buf;
+                       ret = rtl28xxu_ctrl_msg(d, &req);
                }
        } else if (num == 1 && !(msg[0].flags & I2C_M_RD)) {
                if (msg[0].len > 22) {
+                       /* TODO: check msg[0].len max */
                        ret = -EOPNOTSUPP;
                        goto err_unlock;
-               }
-               if (msg[0].addr == 0x10) {
-                       /* integrated demod */
-                       req.value = (msg[0].buf[1] << 8) | (msg[0].addr << 1);
-                       req.index = CMD_DEMOD_WR | msg[0].buf[0];
-                       req.size = msg[0].len-2;
-                       req.data = &msg[0].buf[2];
-                       ret = rtl28xxu_ctrl_msg(d, &req);
-               } else {
-                       /* real I2C */
+               } else if (msg[0].addr == 0x10) {
+                       /* method 1 - integrated demod */
+                       if (msg[0].buf[0] == 0x00) {
+                               /* save demod page for later demod access */
+                               priv->page = msg[0].buf[1];
+                               ret = 0;
+                       } else {
+                               req.value = (msg[0].buf[0] << 8) |
+                                       (msg[0].addr << 1);
+                               req.index = CMD_DEMOD_WR | priv->page;
+                               req.size = msg[0].len-1;
+                               req.data = &msg[0].buf[1];
+                               ret = rtl28xxu_ctrl_msg(d, &req);
+                       }
+               } else if (msg[0].len < 23) {
+                       /* method 2 - old I2C */
                        req.value = (msg[0].buf[0] << 8) | (msg[0].addr << 1);
                        req.index = CMD_I2C_WR;
                        req.size = msg[0].len-1;
                        req.data = &msg[0].buf[1];
                        ret = rtl28xxu_ctrl_msg(d, &req);
+               } else {
+                       /* method 3 - new I2C */
+                       req.value = (msg[0].addr << 1);
+                       req.index = CMD_I2C_DA_WR;
+                       req.size = msg[0].len;
+                       req.data = msg[0].buf;
+                       ret = rtl28xxu_ctrl_msg(d, &req);
                }
        } else {
                ret = -EINVAL;

diff --git a/drivers/media/dvb/dvb-usb/rtl28xxu.h b/drivers/media/dvb/dvb-usb/rtl28xxu.h
index dbde378..2047b1b 100644 (file)
--- a/drivers/media/dvb/dvb-usb/rtl28xxu.h
+++ b/drivers/media/dvb/dvb-usb/rtl28xxu.h
@@ -49,25 +49,30 @@
  * USB commands
  * (usb_control_msg() index parameter)
  */
-#define DEMOD (0x00 << 8)
-#define USB   (0x01 << 8)
-#define SYS   (0x02 << 8)
-#define I2C   (0x03 << 8)
+#define DEMOD  (0x00 << 8)
+#define USB    (0x01 << 8)
+#define SYS    (0x02 << 8)
+#define I2C    (0x03 << 8)
+#define I2C_DA (0x06 << 8)
+
 #define CMD_WR_FLAG   0x10
 #define CMD_DEMOD_RD  (DEMOD)
 #define CMD_DEMOD_WR  (DEMOD | CMD_WR_FLAG)
 #define CMD_USB_RD    (USB)
 #define CMD_USB_WR    (USB | CMD_WR_FLAG)
 #define CMD_SYS_RD    (SYS)
+#define CMD_IR_RD     (CMD_SYS_RD | 0x01)
+#define CMD_IR_WR     (CMD_SYS_WR | 0x01)
 #define CMD_SYS_WR    (SYS | CMD_WR_FLAG)
 #define CMD_I2C_RD    (I2C)
 #define CMD_I2C_WR    (I2C | CMD_WR_FLAG)
-#define CMD_IR_RD     (CMD_SYS_RD | 0x01)
-#define CMD_IR_WR     (CMD_SYS_WR | 0x01)
+#define CMD_I2C_DA_RD (I2C_DA)
+#define CMD_I2C_DA_WR (I2C_DA | CMD_WR_FLAG)
 
 struct rtl28xxu_priv {
        u8 chip_id;
        u8 tuner;
+       u8 page; /* integrated demod active register page */
        bool rc_active;
 };