2018-02-04 21:35:17

by Philippe Cornu

Subject: [PATCH] drm/bridge/synopsys: dsi: Add read feature

This patch adds the DCS/GENERIC DSI read feature.

Signed-off-by: Philippe Cornu <[email protected]>
---
Extra notes:
DSI read tests have been performed with DCS & GENERIC, short & long
commands, on two different panels.
The maximum fifo size (32*32-bit = 128 bytes on stm32) has been
verified too.

drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 58 +++++++++++++++++++++------
1 file changed, 45 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index e9422d05e897..65aeb3f78b48 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -397,18 +397,46 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word));
}

+static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
+ const struct mipi_dsi_msg *msg)
+{
+ int i, j, ret, len = msg->rx_len;
+ u8 *buf = msg->rx_buf;
+ u32 val;
+
+ /* Wait end of the read operation */
+ ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
+ val, !(val & GEN_RD_CMD_BUSY),
+ 1000, CMD_PKT_STATUS_TIMEOUT_US);
+ if (ret) {
+ dev_err(dsi->dev, "Timeout during read operation\n");
+ return ret;
+ }
+
+ for (i = 0; i < len; i += 4) {
+ /* Read fifo must not be empty before all bytes are read */
+ ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
+ val, !(val & GEN_PLD_R_EMPTY),
+ 1000, CMD_PKT_STATUS_TIMEOUT_US);
+ if (ret) {
+ dev_err(dsi->dev, "Read payload FIFO is empty\n");
+ return ret;
+ }
+
+ val = dsi_read(dsi, DSI_GEN_PLD_DATA);
+ for (j = 0; j < 4 && j + i < len; j++)
+ buf[i + j] = val >> (8 * j);
+ }
+
+ return ret;
+}
+
static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
const struct mipi_dsi_msg *msg)
{
struct dw_mipi_dsi *dsi = host_to_dsi(host);
struct mipi_dsi_packet packet;
- int ret;
-
- if (msg->rx_buf || msg->rx_len) {
- /* TODO dw drv improvements: implement read feature */
- dev_warn(dsi->dev, "read operations not yet implemented\n");
- return -EINVAL;
- }
+ int ret, nb_bytes;

ret = mipi_dsi_create_packet(&packet, msg);
if (ret) {
@@ -422,12 +450,16 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
if (ret)
return ret;

- /*
- * TODO Only transmitted size is returned as actual driver does
- * not support dcs/generic reads. Please update return value when
- * delivering the read feature.
- */
- return packet.size;
+ if (msg->rx_buf && msg->rx_len) {
+ ret = dw_mipi_dsi_read(dsi, msg);
+ if (ret)
+ return ret;
+ nb_bytes = msg->rx_len;
+ } else {
+ nb_bytes = packet.size;
+ }
+
+ return nb_bytes;
}

static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
--
2.15.1

2018-02-05 10:08:33

by Andrzej Hajda

Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature

On 04.02.2018 22:31, Philippe Cornu wrote:
> This patch adds the DCS/GENERIC DSI read feature.
>
> Signed-off-by: Philippe Cornu <[email protected]>

Reviewed-by: Andrzej Hajda <[email protected]>

If there will be no objections I will merge it at the end of the week.

 --
Regards
Andrzej

> ---
> Extra notes:
> DSI read tests have been performed with DCS & GENERIC, short & long
> commands, on two different panels.
> The maximum fifo size (32*32-bit = 128 bytes on stm32) has been
> verified too.
>
> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 58 +++++++++++++++++++++------
> 1 file changed, 45 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index e9422d05e897..65aeb3f78b48 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -397,18 +397,46 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
> return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word));
> }
>
> +static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
> + const struct mipi_dsi_msg *msg)
> +{
> + int i, j, ret, len = msg->rx_len;
> + u8 *buf = msg->rx_buf;
> + u32 val;
> +
> + /* Wait end of the read operation */
> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> + val, !(val & GEN_RD_CMD_BUSY),
> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
> + if (ret) {
> + dev_err(dsi->dev, "Timeout during read operation\n");
> + return ret;
> + }
> +
> + for (i = 0; i < len; i += 4) {
> + /* Read fifo must not be empty before all bytes are read */
> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> + val, !(val & GEN_PLD_R_EMPTY),
> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
> + if (ret) {
> + dev_err(dsi->dev, "Read payload FIFO is empty\n");
> + return ret;
> + }
> +
> + val = dsi_read(dsi, DSI_GEN_PLD_DATA);
> + for (j = 0; j < 4 && j + i < len; j++)
> + buf[i + j] = val >> (8 * j);
> + }
> +
> + return ret;
> +}
> +
> static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
> const struct mipi_dsi_msg *msg)
> {
> struct dw_mipi_dsi *dsi = host_to_dsi(host);
> struct mipi_dsi_packet packet;
> - int ret;
> -
> - if (msg->rx_buf || msg->rx_len) {
> - /* TODO dw drv improvements: implement read feature */
> - dev_warn(dsi->dev, "read operations not yet implemented\n");
> - return -EINVAL;
> - }
> + int ret, nb_bytes;
>
> ret = mipi_dsi_create_packet(&packet, msg);
> if (ret) {
> @@ -422,12 +450,16 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
> if (ret)
> return ret;
>
> - /*
> - * TODO Only transmitted size is returned as actual driver does
> - * not support dcs/generic reads. Please update return value when
> - * delivering the read feature.
> - */
> - return packet.size;
> + if (msg->rx_buf && msg->rx_len) {
> + ret = dw_mipi_dsi_read(dsi, msg);
> + if (ret)
> + return ret;
> + nb_bytes = msg->rx_len;
> + } else {
> + nb_bytes = packet.size;
> + }
> +
> + return nb_bytes;
> }
>
> static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {

2018-02-05 12:55:38

by Philippe Cornu

Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature

Hi Andrzej,

And many thanks
Philippe :-)

On 02/05/2018 11:07 AM, Andrzej Hajda wrote:
> On 04.02.2018 22:31, Philippe Cornu wrote:
>> This patch adds the DCS/GENERIC DSI read feature.
>>
>> Signed-off-by: Philippe Cornu <[email protected]>
>
> Reviewed-by: Andrzej Hajda <[email protected]>
>
> If there will be no objections I will merge it at the end of the week.
>
>  --
> Regards
> Andrzej
>
>> ---
>> Extra notes:
>> DSI read tests have been performed with DCS & GENERIC, short & long
>> commands, on two different panels.
>> The maximum fifo size (32*32-bit = 128 bytes on stm32) has been
>> verified too.
>>
>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 58 +++++++++++++++++++++------
>> 1 file changed, 45 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> index e9422d05e897..65aeb3f78b48 100644
>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> @@ -397,18 +397,46 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
>> return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word));
>> }
>>
>> +static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
>> + const struct mipi_dsi_msg *msg)
>> +{
>> + int i, j, ret, len = msg->rx_len;
>> + u8 *buf = msg->rx_buf;
>> + u32 val;
>> +
>> + /* Wait end of the read operation */
>> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>> + val, !(val & GEN_RD_CMD_BUSY),
>> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
>> + if (ret) {
>> + dev_err(dsi->dev, "Timeout during read operation\n");
>> + return ret;
>> + }
>> +
>> + for (i = 0; i < len; i += 4) {
>> + /* Read fifo must not be empty before all bytes are read */
>> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>> + val, !(val & GEN_PLD_R_EMPTY),
>> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
>> + if (ret) {
>> + dev_err(dsi->dev, "Read payload FIFO is empty\n");
>> + return ret;
>> + }
>> +
>> + val = dsi_read(dsi, DSI_GEN_PLD_DATA);
>> + for (j = 0; j < 4 && j + i < len; j++)
>> + buf[i + j] = val >> (8 * j);
>> + }
>> +
>> + return ret;
>> +}
>> +
>> static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
>> const struct mipi_dsi_msg *msg)
>> {
>> struct dw_mipi_dsi *dsi = host_to_dsi(host);
>> struct mipi_dsi_packet packet;
>> - int ret;
>> -
>> - if (msg->rx_buf || msg->rx_len) {
>> - /* TODO dw drv improvements: implement read feature */
>> - dev_warn(dsi->dev, "read operations not yet implemented\n");
>> - return -EINVAL;
>> - }
>> + int ret, nb_bytes;
>>
>> ret = mipi_dsi_create_packet(&packet, msg);
>> if (ret) {
>> @@ -422,12 +450,16 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
>> if (ret)
>> return ret;
>>
>> - /*
>> - * TODO Only transmitted size is returned as actual driver does
>> - * not support dcs/generic reads. Please update return value when
>> - * delivering the read feature.
>> - */
>> - return packet.size;
>> + if (msg->rx_buf && msg->rx_len) {
>> + ret = dw_mipi_dsi_read(dsi, msg);
>> + if (ret)
>> + return ret;
>> + nb_bytes = msg->rx_len;
>> + } else {
>> + nb_bytes = packet.size;
>> + }
>> +
>> + return nb_bytes;
>> }
>>
>> static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
>
>

2018-02-06 01:55:03

by Brian Norris

Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature

Hi,

On Sun, Feb 04, 2018 at 10:31:04PM +0100, Philippe Cornu wrote:
> This patch adds the DCS/GENERIC DSI read feature.
>
> Signed-off-by: Philippe Cornu <[email protected]>
> ---
> Extra notes:
> DSI read tests have been performed with DCS & GENERIC, short & long
> commands, on two different panels.
> The maximum fifo size (32*32-bit = 128 bytes on stm32) has been
> verified too.

Seems OK to me, just comparing with work we've been borrowing from
Rockchip:

https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/863347

(And in fact, it looks much better than that.)

So FWIW:

Reviewed-by: Brian Norris <[email protected]>

and thanks a bunch!

Brian

> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 58 +++++++++++++++++++++------
> 1 file changed, 45 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index e9422d05e897..65aeb3f78b48 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -397,18 +397,46 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
> return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word));
> }
>
> +static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
> + const struct mipi_dsi_msg *msg)
> +{
> + int i, j, ret, len = msg->rx_len;
> + u8 *buf = msg->rx_buf;
> + u32 val;
> +
> + /* Wait end of the read operation */
> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> + val, !(val & GEN_RD_CMD_BUSY),
> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
> + if (ret) {
> + dev_err(dsi->dev, "Timeout during read operation\n");
> + return ret;
> + }
> +
> + for (i = 0; i < len; i += 4) {
> + /* Read fifo must not be empty before all bytes are read */
> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> + val, !(val & GEN_PLD_R_EMPTY),
> + 1000, CMD_PKT_STATUS_TIMEOUT_US);
> + if (ret) {
> + dev_err(dsi->dev, "Read payload FIFO is empty\n");
> + return ret;
> + }
> +
> + val = dsi_read(dsi, DSI_GEN_PLD_DATA);
> + for (j = 0; j < 4 && j + i < len; j++)
> + buf[i + j] = val >> (8 * j);
> + }
> +
> + return ret;
> +}
> +
> static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
> const struct mipi_dsi_msg *msg)
> {
> struct dw_mipi_dsi *dsi = host_to_dsi(host);
> struct mipi_dsi_packet packet;
> - int ret;
> -
> - if (msg->rx_buf || msg->rx_len) {
> - /* TODO dw drv improvements: implement read feature */
> - dev_warn(dsi->dev, "read operations not yet implemented\n");
> - return -EINVAL;
> - }
> + int ret, nb_bytes;
>
> ret = mipi_dsi_create_packet(&packet, msg);
> if (ret) {
> @@ -422,12 +450,16 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
> if (ret)
> return ret;
>
> - /*
> - * TODO Only transmitted size is returned as actual driver does
> - * not support dcs/generic reads. Please update return value when
> - * delivering the read feature.
> - */
> - return packet.size;
> + if (msg->rx_buf && msg->rx_len) {
> + ret = dw_mipi_dsi_read(dsi, msg);
> + if (ret)
> + return ret;
> + nb_bytes = msg->rx_len;
> + } else {
> + nb_bytes = packet.size;
> + }
> +
> + return nb_bytes;
> }
>
> static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
> --
> 2.15.1
>

2018-02-08 07:41:02

by Andrzej Hajda

Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature

On 04.02.2018 22:31, Philippe Cornu wrote:
> This patch adds the DCS/GENERIC DSI read feature.
>
> Signed-off-by: Philippe Cornu <[email protected]>
> ---
Queued to drm-misc-next.
--
Regards
Andrzej

2018-02-08 08:37:36

by Philippe Cornu

Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature

Many thanks
Philippe :-)

On 02/08/2018 08:39 AM, Andrzej Hajda wrote:
> On 04.02.2018 22:31, Philippe Cornu wrote:
>> This patch adds the DCS/GENERIC DSI read feature.
>>
>> Signed-off-by: Philippe Cornu <[email protected]>
>> ---
> Queued to drm-misc-next.
> --
> Regards
> Andrzej
>