Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ad30e91b authored by Antti Palosaari's avatar Antti Palosaari Committed by Mauro Carvalho Chehab
Browse files

[media] af9035: fix and enhance I2C adapter 



There was a bug I2C adapter writes and reads one byte too much.
As the most I2C clients has auto-increment register addressing
this leads next register from the target register overwritten by
garbage data.

As a change remove whole register address byte usage and write
data directly to the I2C bus without saying what are register
address bytes to firmware.

Signed-off-by: default avatarAntti Palosaari <crope@iki.fi>
Cc: Michael Buesch <m@bues.ch>
Cc: Hans-Frieder Vogt <hfvogt@gmx.net>
Cc: Gianluca Gennari <gennarone@gmail.com>
Tested-by: default avatarMichael Buesch <m@bues.ch>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent 48bf7e1a

drivers/media/dvb/dvb-usb/af9035.c

+26 −8
Original line number Original line Diff line number Diff line
@@ -224,6 +224,22 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap, 
	if (mutex_lock_interruptible(&d->i2c_mutex) < 0)

	if (mutex_lock_interruptible(&d->i2c_mutex) < 0)

		return -EAGAIN;

		return -EAGAIN;





	/*

	 * I2C sub header is 5 bytes long. Meaning of those bytes are:

	 * 0: data len

	 * 1: I2C addr << 1

	 * 2: reg addr len

	 *    byte 3 and 4 can be used as reg addr

	 * 3: reg addr MSB

	 *    used when reg addr len is set to 2

	 * 4: reg addr LSB

	 *    used when reg addr len is set to 1 or 2

	 *

	 * For the simplify we do not use register addr at all.

	 * NOTE: As a firmware knows tuner type there is very small possibility

	 * there could be some tuner I2C hacks done by firmware and this may

	 * lead problems if firmware expects those bytes are used.

	 */

	if (num == 2 && !(msg[0].flags & I2C_M_RD) &&

	if (num == 2 && !(msg[0].flags & I2C_M_RD) &&

			(msg[1].flags & I2C_M_RD)) {

			(msg[1].flags & I2C_M_RD)) {

		if (msg[0].len > 40 || msg[1].len > 40) {

		if (msg[0].len > 40 || msg[1].len > 40) {
@@ -237,14 +253,15 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap, 
					msg[1].len);

					msg[1].len);

		} else {

		} else {

			/* I2C */

			/* I2C */

			u8 buf[4 + msg[0].len];

			u8 buf[5 + msg[0].len];

			struct usb_req req = { CMD_I2C_RD, 0, sizeof(buf),

			struct usb_req req = { CMD_I2C_RD, 0, sizeof(buf),

					buf, msg[1].len, msg[1].buf };

					buf, msg[1].len, msg[1].buf };

			buf[0] = msg[1].len;

			buf[0] = msg[1].len;

			buf[1] = msg[0].addr << 1;

			buf[1] = msg[0].addr << 1;

			buf[2] = 0x01;

			buf[2] = 0x00; /* reg addr len */

			buf[3] = 0x00;

			buf[3] = 0x00; /* reg addr MSB */

			memcpy(&buf[4], msg[0].buf, msg[0].len);

			buf[4] = 0x00; /* reg addr LSB */

			memcpy(&buf[5], msg[0].buf, msg[0].len);

			ret = af9035_ctrl_msg(d->udev, &req);

			ret = af9035_ctrl_msg(d->udev, &req);

		}

		}

	} else if (num == 1 && !(msg[0].flags & I2C_M_RD)) {

	} else if (num == 1 && !(msg[0].flags & I2C_M_RD)) {
@@ -259,14 +276,15 @@ static int af9035_i2c_master_xfer(struct i2c_adapter *adap, 
					msg[0].len - 3);

					msg[0].len - 3);

		} else {

		} else {

			/* I2C */

			/* I2C */

			u8 buf[4 + msg[0].len];

			u8 buf[5 + msg[0].len];

			struct usb_req req = { CMD_I2C_WR, 0, sizeof(buf), buf,

			struct usb_req req = { CMD_I2C_WR, 0, sizeof(buf), buf,

					0, NULL };

					0, NULL };

			buf[0] = msg[0].len;

			buf[0] = msg[0].len;

			buf[1] = msg[0].addr << 1;

			buf[1] = msg[0].addr << 1;

			buf[2] = 0x01;

			buf[2] = 0x00; /* reg addr len */

			buf[3] = 0x00;

			buf[3] = 0x00; /* reg addr MSB */

			memcpy(&buf[4], msg[0].buf, msg[0].len);

			buf[4] = 0x00; /* reg addr LSB */

			memcpy(&buf[5], msg[0].buf, msg[0].len);

			ret = af9035_ctrl_msg(d->udev, &req);

			ret = af9035_ctrl_msg(d->udev, &req);

		}

		}

	} else {

	} else {