On Sun, Dec 11, 2011 at 11:10:10PM -0500, Yuantian.tang@xxxxxxxxxxxxx wrote:
> From: Tang Yuantian <B29983@xxxxxxxxxxxxx>
>
> Add support for SMBUS_READ_BLOCK_DATA to the i2c-mpc bus driver.
>
> Signed-off-by: Tang Yuantian <Yuantian.Tang@xxxxxxxxxxxxx>
> Signed-off-by: Guenter Roeck <guenter.roeck@xxxxxxxxxxxx>
You can not do this. While I may have written this patch originally,
I abandoned it, and you can not use my signature.
Guenter
> ---
> tested on p1022ds
>
> drivers/i2c/busses/i2c-mpc.c | 63 ++++++++++++++++++++++++++++++++---------
> 1 files changed, 49 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
> index 107397a..bba9a07 100644
> --- a/drivers/i2c/busses/i2c-mpc.c
> +++ b/drivers/i2c/busses/i2c-mpc.c
> @@ -454,7 +454,7 @@ static int mpc_write(struct mpc_i2c *i2c, int target,
> }
>
> static int mpc_read(struct mpc_i2c *i2c, int target,
> - u8 *data, int length, int restart)
> + u8 *data, int length, int restart, bool recv_len)
> {
> unsigned timeout = i2c->adap.timeout;
> int i, result;
> @@ -470,7 +470,7 @@ static int mpc_read(struct mpc_i2c *i2c, int target,
> return result;
>
> if (length) {
> - if (length == 1)
> + if (length == 1 && !recv_len)
> writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
> else
> writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA);
> @@ -479,17 +479,46 @@ static int mpc_read(struct mpc_i2c *i2c, int target,
> }
>
> for (i = 0; i < length; i++) {
> + u8 byte;
> +
> result = i2c_wait(i2c, timeout, 0);
> if (result < 0)
> return result;
>
> - /* Generate txack on next to last byte */
> - if (i == length - 2)
> - writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
> - /* Do not generate stop on last byte */
> - if (i == length - 1)
> - writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX);
> - data[i] = readb(i2c->base + MPC_I2C_DR);
> + /*
> + * For block reads, we have to know the total length (1st byte)
> + * before we can determine if we are done.
> + */
> + if (i || !recv_len) {
> + /* Generate txack on next to last byte */
> + if (i == length - 2)
> + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
> + | CCR_TXAK);
> + /* Do not generate stop on last byte */
> + if (i == length - 1)
> + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
> + | CCR_MTX);
> + }
> +
> + byte = readb(i2c->base + MPC_I2C_DR);
> +
> + /*
> + * Adjust length if first received byte is length.
> + * The length is 1 length byte plus actually data length
> + */
> + if (i == 0 && recv_len) {
> + if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX)
> + return -EPROTO;
> + length += byte;
> + /*
> + * For block reads, generate txack here if data length
> + * is 1 byte (total length is 2 bytes).
> + */
> + if (length == 2)
> + writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
> + | CCR_TXAK);
> + }
> + data[i] = byte;
> }
>
> return length;
> @@ -532,12 +561,17 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
> "Doing %s %d bytes to 0x%02x - %d of %d messages\n",
> pmsg->flags & I2C_M_RD ? "read" : "write",
> pmsg->len, pmsg->addr, i + 1, num);
> - if (pmsg->flags & I2C_M_RD)
> - ret =
> - mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
> - else
> + if (pmsg->flags & I2C_M_RD) {
> + bool recv_len = pmsg->flags & I2C_M_RECV_LEN;
> +
> + ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i,
> + recv_len);
> + if (recv_len && ret > 0)
> + pmsg->len = ret;
> + } else {
> ret =
> mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
> + }
> }
> mpc_i2c_stop(i2c);
> return (ret < 0) ? ret : num;
> @@ -545,7 +579,8 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
>
> static u32 mpc_functionality(struct i2c_adapter *adap)
> {
> - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
> + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
> + | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
> }
>
> static const struct i2c_algorithm mpc_algo = {
> --
> 1.6.4
>
>
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