[PATCH] drm/mipi-dsi: Reduce driver bloat of mipi_dsi_*_write_seq()
Douglas Anderson
dianders at chromium.org
Thu Apr 25 00:20:18 UTC 2024
The consensus of many DRM folks is that we want to move away from DSI
drivers defining tables of init commands. Instead, we want to move to
init functions that can use common DRM functions. The issue thus far
has been that using the macros mipi_dsi_generic_write_seq() and
mipi_dsi_dcs_write_seq() bloats the driver using them.
Through a cooperative effort between Hsin-Yi Wang and Dmitry
Baryshkov, we have realized that the majority of the bloat is the fact
that we have the dev_err_ratelimited() directly in the macros. Let's
hoist this call into drm_mipi_dsi.c by adding a "chatty" version of
the functions that includes the print.
Without any changes to clients this gives a dramatic savings. Building
with my build system shows one example:
$ scripts/bloat-o-meter \
.../before/panel-novatek-nt36672e.ko \
.../after/panel-novatek-nt36672e.ko
add/remove: 0/1 grow/shrink: 1/1 up/down: 6/-19652 (-19646)
Function old new delta
__UNIQUE_ID_vermagic520 64 70 +6
nt36672e_1080x2408_60hz_init 16592 7260 -9332
nt36672e_1080x2408_60hz_init._rs 10320 - -10320
Total: Before=31503, After=11857, chg -62.36%
Note that given the change in location of the print it's harder to
include the "cmd" in the printout for mipi_dsi_dcs_write_seq() since,
theoretically, someone could call the new chatty function with a
zero-size array and it would be illegal to dereference data[0].
There's a printk format to print the whole buffer and this is probably
more useful for debugging anyway. Given that we're doing this for
mipi_dsi_dcs_write_seq(), let's also print the buffer for
mipi_dsi_generic_write_seq() in the error case.
Signed-off-by: Douglas Anderson <dianders at chromium.org>
---
The MIPI device I have in front of me (wormdingler) hasn't been
converted to use these functions yet, so this is just compile
tested. It's about my end of day so I'm sending this out since it's
pretty straightforward. Hopefully others can confirm it works well for
them and also saves space under their compilers.
drivers/gpu/drm/drm_mipi_dsi.c | 54 ++++++++++++++++++++++++++++++++++
include/drm/drm_mipi_dsi.h | 31 ++++++++-----------
2 files changed, 67 insertions(+), 18 deletions(-)
diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index 795001bb7ff1..5ded6aef38ed 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -764,6 +764,33 @@ ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, const void *payload,
}
EXPORT_SYMBOL(mipi_dsi_generic_write);
+/**
+ * mipi_dsi_generic_write_chatty() - mipi_dsi_generic_write() w/ an error log
+ * @dsi: DSI peripheral device
+ * @payload: buffer containing the payload
+ * @size: size of payload buffer
+ *
+ * Just like mipi_dsi_generic_write() but includes a dev_err_ratelimited()
+ * call for you.
+ *
+ * Return: The number of bytes transmitted on success or a negative error code
+ * on failure.
+ */
+ssize_t mipi_dsi_generic_write_chatty(struct mipi_dsi_device *dsi,
+ const void *payload, size_t size)
+{
+ struct device *dev = &dsi->dev;
+ int ret;
+
+ ret = mipi_dsi_generic_write(dsi, payload, size);
+ if (ret < 0)
+ dev_err_ratelimited(dev, "sending generic data %*ph failed: %d\n",
+ (int)size, payload, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL(mipi_dsi_generic_write_chatty);
+
/**
* mipi_dsi_generic_read() - receive data using a generic read packet
* @dsi: DSI peripheral device
@@ -852,6 +879,33 @@ ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
}
EXPORT_SYMBOL(mipi_dsi_dcs_write_buffer);
+/**
+ * mipi_dsi_dcs_write_buffer_chatty - mipi_dsi_dcs_write_buffer() w/ an error log
+ * @dsi: DSI peripheral device
+ * @data: buffer containing data to be transmitted
+ * @len: size of transmission buffer
+ *
+ * Just like mipi_dsi_dcs_write_buffer() but includes a dev_err_ratelimited()
+ * call for you.
+ *
+ * Return: The number of bytes successfully transmitted or a negative error
+ * code on failure.
+ */
+ssize_t mipi_dsi_dcs_write_buffer_chatty(struct mipi_dsi_device *dsi,
+ const void *data, size_t len)
+{
+ struct device *dev = &dsi->dev;
+ int ret;
+
+ ret = mipi_dsi_dcs_write_buffer(dsi, data, len);
+ if (ret < 0)
+ dev_err_ratelimited(dev, "sending dcs data %*ph failed: %d\n",
+ (int)len, data, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL(mipi_dsi_dcs_write_buffer_chatty);
+
/**
* mipi_dsi_dcs_write() - send DCS write command
* @dsi: DSI peripheral device
diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
index 82b1cc434ea3..784e425dc4c8 100644
--- a/include/drm/drm_mipi_dsi.h
+++ b/include/drm/drm_mipi_dsi.h
@@ -256,6 +256,8 @@ int mipi_dsi_picture_parameter_set(struct mipi_dsi_device *dsi,
ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, const void *payload,
size_t size);
+ssize_t mipi_dsi_generic_write_chatty(struct mipi_dsi_device *dsi,
+ const void *payload, size_t size);
ssize_t mipi_dsi_generic_read(struct mipi_dsi_device *dsi, const void *params,
size_t num_params, void *data, size_t size);
@@ -279,6 +281,8 @@ enum mipi_dsi_dcs_tear_mode {
ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
const void *data, size_t len);
+ssize_t mipi_dsi_dcs_write_buffer_chatty(struct mipi_dsi_device *dsi,
+ const void *data, size_t len);
ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd,
const void *data, size_t len);
ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
@@ -317,14 +321,10 @@ int mipi_dsi_dcs_get_display_brightness_large(struct mipi_dsi_device *dsi,
#define mipi_dsi_generic_write_seq(dsi, seq...) \
do { \
static const u8 d[] = { seq }; \
- struct device *dev = &dsi->dev; \
int ret; \
- ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)); \
- if (ret < 0) { \
- dev_err_ratelimited(dev, "transmit data failed: %d\n", \
- ret); \
+ ret = mipi_dsi_generic_write_chatty(dsi, d, ARRAY_SIZE(d)); \
+ if (ret < 0) \
return ret; \
- } \
} while (0)
/**
@@ -333,18 +333,13 @@ int mipi_dsi_dcs_get_display_brightness_large(struct mipi_dsi_device *dsi,
* @cmd: Command
* @seq: buffer containing data to be transmitted
*/
-#define mipi_dsi_dcs_write_seq(dsi, cmd, seq...) \
- do { \
- static const u8 d[] = { cmd, seq }; \
- struct device *dev = &dsi->dev; \
- int ret; \
- ret = mipi_dsi_dcs_write_buffer(dsi, d, ARRAY_SIZE(d)); \
- if (ret < 0) { \
- dev_err_ratelimited( \
- dev, "sending command %#02x failed: %d\n", \
- cmd, ret); \
- return ret; \
- } \
+#define mipi_dsi_dcs_write_seq(dsi, cmd, seq...) \
+ do { \
+ static const u8 d[] = { cmd, seq }; \
+ int ret; \
+ ret = mipi_dsi_dcs_write_buffer_chatty(dsi, d, ARRAY_SIZE(d)); \
+ if (ret < 0) \
+ return ret; \
} while (0)
/**
--
2.44.0.769.g3c40516874-goog
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