On Thu, Sep 19, 2024 at 5:20 PM Hermes Wu <Hermes.Wu@xxxxxxxxxx> wrote:
>
> From: "Hermes.Wu" <Hermes.wu@xxxxxxxxxx>
>
> add AUX-I2C functionality to support MCCS.
>
> Change-Id: I63e1a0e5da67526f89f35605a82944be67dee8ac
Remove the Change-Id line. If you run scripts/checkpatch.pl, the
script should catch this for you.
> Signed-off-by: Hermes Wu <Hermes.wu@xxxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/ite-it6505.c | 209 ++++++++++++++++++++++++++--
> 1 file changed, 200 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> index cef02c8c363e..1a272c67e82b 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -127,6 +127,9 @@
> #define REG_AUX_ADR_16_19 0x26
> #define REG_AUX_OUT_DATA0 0x27
>
> +#define REG_AUX_I2C_ADR 0x25
> +#define REG_AUX_I2C_OP 0x26
> +
> #define REG_AUX_CMD_REQ 0x2B
> #define AUX_BUSY BIT(5)
>
> @@ -268,6 +271,19 @@
> #define REG_SSC_CTRL1 0x189
> #define REG_SSC_CTRL2 0x18A
>
> +#define REG_AUX_USER_CTRL 0x190
> +#define EN_USER_AUX BIT(0)
> +#define USER_AUX_DONE BIT(1)
> +#define AUX_EVENT BIT(4)
> +
> +#define REG_AUX_USER_DATA_REC 0x191
> +#define M_AUX_IN_REC 0xF0
> +#define M_AUX_OUT_REC 0x0F
> +
> +#define REG_AUX_USER_TXB 0x190
> +#define REG_AUX_USER_REPLY 0x19A
> +#define REG_AUX_USER_RXB(n) (n + 0x19B)
> +
> #define RBR DP_LINK_BW_1_62
> #define HBR DP_LINK_BW_2_7
> #define HBR2 DP_LINK_BW_5_4
> @@ -303,6 +319,8 @@
> #define MAX_EQ_LEVEL 0x03
> #define AUX_WAIT_TIMEOUT_MS 15
> #define AUX_FIFO_MAX_SIZE 16
> +#define AUX_I2C_MAX_SIZE 4
> +#define AUX_I2C_DEFER_RETRY 4
> #define PIXEL_CLK_DELAY 1
> #define PIXEL_CLK_INVERSE 0
> #define ADJUST_PHASE_THRESHOLD 80000
> @@ -325,7 +343,12 @@
> enum aux_cmd_type {
> CMD_AUX_NATIVE_READ = 0x0,
> CMD_AUX_NATIVE_WRITE = 0x5,
> + CMD_AUX_GI2C_ADR = 0x08,
> + CMD_AUX_GI2C_READ = 0x09,
> + CMD_AUX_GI2C_WRITE = 0x0A,
> CMD_AUX_I2C_EDID_READ = 0xB,
> + CMD_AUX_I2C_READ = 0x0D,
> + CMD_AUX_I2C_WRITE = 0x0C,
>
> /*extend read ncommand */
> CMD_AUX_GET_KSV_LIST = 0x10,
> @@ -333,8 +356,11 @@ enum aux_cmd_type {
>
> enum aux_cmd_reply {
> REPLY_ACK,
> - REPLY_NACK,
> - REPLY_DEFER,
> + REPLY_NACK = 1,
> + REPLY_DEFER = 2,
> +
> + REPLY_I2C_NACK = 4,
> + REPLY_I2C_DEFER = 8,
> };
>
> enum link_train_status {
> @@ -1087,7 +1113,6 @@ static ssize_t it6505_aux_do_transfer(struct it6505 *it6505,
> size_t size, enum aux_cmd_reply *reply)
> {
> int i, ret_size, ret = 0, request_size;
> - struct device *dev = &it6505->client->dev;
The drm-misc/drm-misc-next doesn't have it6505->client node. It's
already removed at commit d65feac281ab ("drm/bridge: Remove redundant
i2c_client in anx7625/it6505").
Please rebase your patch.
>
> mutex_lock(&it6505->aux_lock);
> for (i = 0; i < size; ) {
> @@ -1114,6 +1139,168 @@ static ssize_t it6505_aux_do_transfer(struct it6505 *it6505,
> return ret;
> }
>
> +
> +static int it6505_aux_i2c_wait(struct it6505 *it6505, u8 *reply)
> +{
> + int err = 0;
> + unsigned long timeout;
> + struct device *dev = &it6505->client->dev;
> +
> + timeout = jiffies + msecs_to_jiffies(AUX_WAIT_TIMEOUT_MS) + 1;
> +
> + do {
> + if (it6505_read(it6505, REG_AUX_USER_CTRL) & AUX_EVENT)
Do we need to assign err if it6505_read returns error?
> + break;
> + if (time_after(jiffies, timeout)) {
> + dev_err(dev, "Timed out waiting AUX I2C, BUSY = %X\n",
> + it6505_aux_op_finished(it6505));
> + err = -ETIMEDOUT;
> + goto end_aux_i2c_wait;
> + }
> + usleep_range(300, 800);
> +
> + } while (!it6505_aux_op_finished(it6505));
Can this loop be changed to regmap_read_poll_timeout()?
> +
> + if (reply == NULL)
> + goto end_aux_i2c_wait;
If reply is NULL, then there will be a NULL pointer dereference at
it6505_aux_i2c_readb() anyway. From the usages in drm_dp_helper.c, I
doubt if this pointer is possible to be NULL. Even if it could, you
should have done this check earlier.
> +
> + *reply = it6505_read(it6505, REG_AUX_USER_REPLY) >> 4;
> +
> + if (*reply == 0)
> + goto end_aux_i2c_wait;
> +
> + if ((*reply == DP_AUX_NATIVE_REPLY_DEFER) ||
> + (*reply == DP_AUX_I2C_REPLY_DEFER))
> + err = -EBUSY;
> + else if ((*reply == DP_AUX_NATIVE_REPLY_NACK) ||
> + (*reply == DP_AUX_I2C_REPLY_NACK))
> + err = -ENXIO;
> +
> +end_aux_i2c_wait:
> + it6505_set_bits(it6505, REG_AUX_USER_CTRL, USER_AUX_DONE, USER_AUX_DONE);
> + return err;
> +}
> +
> +static int it6505_aux_i2c_readb(struct it6505 *it6505, u8 *buf, size_t size, u8 *reply)
> +{
> + int ret, i;
> + int retry = 0;
> +
> + for (retry = 0; retry < AUX_I2C_DEFER_RETRY; retry++) {
> +
Remove the blank line here.
> + it6505_write(it6505, REG_AUX_CMD_REQ, CMD_AUX_GI2C_READ);
> +
> + ret = it6505_aux_i2c_wait(it6505, reply);
> +
> + if ((*reply == DP_AUX_NATIVE_REPLY_DEFER) ||
> + (*reply == DP_AUX_I2C_REPLY_DEFER))
> + continue;
> +
> + if (ret >= 0)
> + break;
Should we check the return value before checking the reply?
> + }
> +
> + for (i = 0; i < size; i++)
> + buf[i] = (u8) it6505_read(it6505, REG_AUX_USER_RXB(0 + i));
> +
> + return size;
> +}
> +
> +static int it6505_aux_i2c_writeb(struct it6505 *it6505, u8 *buf, size_t size, u8 *reply)
> +{
> + int i, ret;
> + int retry = 0;
> +
> + for (i = 0; i < size; i++)
> + it6505_write(it6505, REG_AUX_OUT_DATA0 + i, buf[i]);
> +
> + for (retry = 0; retry < AUX_I2C_DEFER_RETRY; retry++) {
> +
ditto
> + it6505_write(it6505, REG_AUX_CMD_REQ, CMD_AUX_GI2C_WRITE);
> +
> + ret = it6505_aux_i2c_wait(it6505, reply);
> +
> + if ((*reply == DP_AUX_NATIVE_REPLY_DEFER) ||
> + (*reply == DP_AUX_I2C_REPLY_DEFER))
> + continue;
> +
> + if (ret >= 0)
> + break;
ditto
> + }
> + return size;
> +}
> +
> +static ssize_t it6505_aux_i2c_operation(struct it6505 *it6505,
> + struct drm_dp_aux_msg *msg)
> +{
> + int ret;
> + ssize_t request_size, data_cnt = 0;
> + struct device *dev = &it6505->client->dev;
> + u8 *buffer = msg->buffer;
> +
> + /* set AUX user mode */
> + it6505_set_bits(it6505, REG_AUX_CTRL,
> + AUX_USER_MODE | AUX_NO_SEGMENT_WR, AUX_USER_MODE);
> + it6505_set_bits(it6505, REG_AUX_USER_CTRL, EN_USER_AUX, EN_USER_AUX);
> + /* clear AUX FIFO */
> + it6505_set_bits(it6505, REG_AUX_CTRL,
> + AUX_EN_FIFO_READ | CLR_EDID_FIFO,
> + AUX_EN_FIFO_READ | CLR_EDID_FIFO);
> +
> + it6505_set_bits(it6505, REG_AUX_CTRL,
> + AUX_EN_FIFO_READ | CLR_EDID_FIFO, 0x00);
> +
> + it6505_write(it6505, REG_AUX_ADR_0_7, 0x00);
> + it6505_write(it6505, REG_AUX_I2C_ADR, msg->address << 1);
> +
> + if (msg->size == 0) {
> + /* IIC Start/STOP dummy write */
> + it6505_write(it6505, REG_AUX_I2C_OP, msg->request);
> + it6505_write(it6505, REG_AUX_CMD_REQ, CMD_AUX_GI2C_ADR);
> + ret = it6505_aux_i2c_wait(it6505, &msg->reply);
> + goto end_aux_i2c_transfer;
> + }
> +
> + /* IIC data transfer */
> + for (data_cnt = 0; data_cnt < msg->size; ) {
> + request_size = min(msg->size - data_cnt, AUX_I2C_MAX_SIZE);
> + it6505_write(it6505, REG_AUX_I2C_OP,
> + (msg->request) | ((request_size - 1) << 4));
> +
> + if ((msg->request & DP_AUX_I2C_READ) == DP_AUX_I2C_READ)
> + ret = it6505_aux_i2c_readb(it6505, &buffer[data_cnt],
> + request_size, &msg->reply);
> + else
> + ret = it6505_aux_i2c_writeb(it6505, &buffer[data_cnt],
> + request_size, &msg->reply);
> +
Remove the blank line here. I don't think we need a blank line before
the return value check.
> + if (ret < 0)
> + goto end_aux_i2c_transfer;
> +
> + data_cnt += request_size;
> + }
> + ret = data_cnt;
> +end_aux_i2c_transfer:
> +
Remove the blank line.
> + it6505_set_bits(it6505, REG_AUX_USER_CTRL, EN_USER_AUX, 0);
> + it6505_set_bits(it6505, REG_AUX_CTRL, AUX_USER_MODE, 0);
> + return ret;
> +}
> +
> +
Remove one blank line.
> +static ssize_t it6505_aux_i2c_transfer(struct drm_dp_aux *aux,
> + struct drm_dp_aux_msg *msg)
> +{
> + struct it6505 *it6505 = container_of(aux, struct it6505, aux);
> + int ret;
> +
> + mutex_lock(&it6505->aux_lock);
> + ret = it6505_aux_i2c_operation(it6505, msg);
> + mutex_unlock(&it6505->aux_lock);
> + return ret;
> +}
> +
> +
ditto.
> static ssize_t it6505_aux_transfer(struct drm_dp_aux *aux,
> struct drm_dp_aux_msg *msg)
> {
> @@ -1125,7 +1312,7 @@ static ssize_t it6505_aux_transfer(struct drm_dp_aux *aux,
>
> /* IT6505 doesn't support arbitrary I2C read / write. */
Update the comment above.
> if (is_i2c)
> - return -EINVAL;
> + return it6505_aux_i2c_transfer(aux, msg);
>
> switch (msg->request) {
> case DP_AUX_NATIVE_READ:
> @@ -1153,6 +1340,8 @@ static ssize_t it6505_aux_transfer(struct drm_dp_aux *aux,
> case REPLY_DEFER:
> msg->reply = DP_AUX_NATIVE_REPLY_DEFER;
> break;
> + default:
> + break;
> }
>
> return ret;
> @@ -1180,7 +1369,7 @@ static int it6505_get_edid_block(void *data, u8 *buf, unsigned int block,
> switch (reply) {
> case REPLY_ACK:
> DRM_DEV_DEBUG_DRIVER(dev, "[0x%02x]: %8ph", offset,
> - buf + offset);
> + uf + offset);
This looks like a typo to me.
> offset += 8;
> aux_retry = 100;
> break;
> @@ -1190,6 +1379,8 @@ static int it6505_get_edid_block(void *data, u8 *buf, unsigned int block,
> msleep(20);
> if (!(--aux_retry))
> return -EIO;
> + default:
> + break;
> }
> }
>
> @@ -2031,8 +2222,8 @@ static int it6505_setup_sha1_input(struct it6505 *it6505, u8 *sha1_input)
>
>
> err = it6505_get_ksvlist(it6505, sha1_input, down_stream_count * 5);
> - if (err < 0)
> - return err;
> + if (err < 0)
> + return err;
Revert the indentation change here.
>
> msg_count += down_stream_count * 5;
>
> @@ -2075,7 +2266,7 @@ static bool it6505_hdcp_part2_ksvlist_check(struct it6505 *it6505)
> for (retry = 0; retry < 3; retry++) {
>
> err = it6505_get_dpcd(it6505, DP_AUX_HDCP_V_PRIME(0), (u8 *)bv,
> - sizeof(bv));
> + sizeof(bv));
Same here.
>
> if (err < 0) {
> dev_err(dev, "Read V' value Fail %d", retry);
> @@ -2126,7 +2317,7 @@ static void it6505_hdcp_wait_ksv_list(struct work_struct *work)
>
> ksv_list_check = it6505_hdcp_part2_ksvlist_check(it6505);
> DRM_DEV_DEBUG_DRIVER(dev, "ksv list ready, ksv list check %s",
> - ksv_list_check ? "pass" : "fail");
> + ksv_list_check ? "pass" : "fail");
The indentation here is correct on my drm-misc/drm-misc-next checkout.
Please rebase your patch and revisit this.
>
> if (ksv_list_check)
> return;
> --
> 2.34.1
>
Regards,
Pin-yen
