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authorNoralf Trønnes <noralf@tronnes.org>2019-07-19 17:59:11 +0200
committerNoralf Trønnes <noralf@tronnes.org>2019-07-23 15:46:56 +0200
commit083a6c23b9ecf478265bb27ccacb8d587732058e (patch)
tree8eb5c8f95bc4b54f2180375b98d4eb153e87d5f1
parentdrm/tinydrm: Remove tinydrm_spi_max_transfer_size() (diff)
downloadlinux-083a6c23b9ecf478265bb27ccacb8d587732058e.tar.xz
linux-083a6c23b9ecf478265bb27ccacb8d587732058e.zip
drm/tinydrm: Clean up tinydrm_spi_transfer()
Prep work before moving the function to mipi-dbi. tinydrm_spi_transfer() was made to support one class of drivers in drivers/staging/fbtft that has not been converted to DRM yet, so strip away the unused functionality: - Start byte (header) is not used. - No driver relies on the automatic 16-bit byte swapping on little endian machines with SPI controllers only supporting 8 bits per word. Other changes: - No need to initialize ret - No need for the WARN since mipi-dbi only uses 8 and 16 bpw. - Use spi_message_init_with_transfers() Cc: David Lechner <david@lechnology.com> Acked-by: : David Lechner <david@lechnology.com> Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-7-noralf@tronnes.org
-rw-r--r--drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c40
-rw-r--r--drivers/gpu/drm/tinydrm/ili9225.c4
-rw-r--r--drivers/gpu/drm/tinydrm/mipi-dbi.c4
-rw-r--r--include/drm/tinydrm/tinydrm-helpers.h3
4 files changed, 9 insertions, 42 deletions
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
index af5bec8861de..d95eb50fa9d4 100644
--- a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
@@ -24,23 +24,18 @@
* tinydrm_spi_transfer - SPI transfer helper
* @spi: SPI device
* @speed_hz: Override speed (optional)
- * @header: Optional header transfer
* @bpw: Bits per word
* @buf: Buffer to transfer
* @len: Buffer length
*
* This SPI transfer helper breaks up the transfer of @buf into chunks which
- * the SPI master driver can handle. If the machine is Little Endian and the
- * SPI master driver doesn't support 16 bits per word, it swaps the bytes and
- * does a 8-bit transfer.
- * If @header is set, it is prepended to each SPI message.
+ * the SPI controller driver can handle.
*
* Returns:
* Zero on success, negative error code on failure.
*/
int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
- struct spi_transfer *header, u8 bpw, const void *buf,
- size_t len)
+ u8 bpw, const void *buf, size_t len)
{
size_t max_chunk = spi_max_transfer_size(spi);
struct spi_transfer tr = {
@@ -48,43 +43,16 @@ int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
.speed_hz = speed_hz,
};
struct spi_message m;
- u16 *swap_buf = NULL;
size_t chunk;
- int ret = 0;
+ int ret;
- if (WARN_ON_ONCE(bpw != 8 && bpw != 16))
- return -EINVAL;
-
- if (bpw == 16 && !spi_is_bpw_supported(spi, 16)) {
- tr.bits_per_word = 8;
- if (tinydrm_machine_little_endian()) {
- swap_buf = kmalloc(min(len, max_chunk), GFP_KERNEL);
- if (!swap_buf)
- return -ENOMEM;
- }
- }
-
- spi_message_init(&m);
- if (header)
- spi_message_add_tail(header, &m);
- spi_message_add_tail(&tr, &m);
+ spi_message_init_with_transfers(&m, &tr, 1);
while (len) {
chunk = min(len, max_chunk);
tr.tx_buf = buf;
tr.len = chunk;
-
- if (swap_buf) {
- const u16 *buf16 = buf;
- unsigned int i;
-
- for (i = 0; i < chunk / 2; i++)
- swap_buf[i] = swab16(buf16[i]);
-
- tr.tx_buf = swap_buf;
- }
-
buf += chunk;
len -= chunk;
diff --git a/drivers/gpu/drm/tinydrm/ili9225.c b/drivers/gpu/drm/tinydrm/ili9225.c
index 7a8e1b4a37ee..21677e3ed38b 100644
--- a/drivers/gpu/drm/tinydrm/ili9225.c
+++ b/drivers/gpu/drm/tinydrm/ili9225.c
@@ -323,7 +323,7 @@ static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par,
gpiod_set_value_cansleep(mipi->dc, 0);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
- ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1);
+ ret = tinydrm_spi_transfer(spi, speed_hz, 8, cmd, 1);
if (ret || !num)
return ret;
@@ -333,7 +333,7 @@ static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par,
gpiod_set_value_cansleep(mipi->dc, 1);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);
- return tinydrm_spi_transfer(spi, speed_hz, NULL, bpw, par, num);
+ return tinydrm_spi_transfer(spi, speed_hz, bpw, par, num);
}
static const struct drm_simple_display_pipe_funcs ili9225_pipe_funcs = {
diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c
index ae31a5c9aa1b..8fb6ce4ca6fc 100644
--- a/drivers/gpu/drm/tinydrm/mipi-dbi.c
+++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c
@@ -926,7 +926,7 @@ static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 *cmd,
gpiod_set_value_cansleep(mipi->dc, 0);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
- ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1);
+ ret = tinydrm_spi_transfer(spi, speed_hz, 8, cmd, 1);
if (ret || !num)
return ret;
@@ -936,7 +936,7 @@ static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 *cmd,
gpiod_set_value_cansleep(mipi->dc, 1);
speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);
- return tinydrm_spi_transfer(spi, speed_hz, NULL, bpw, par, num);
+ return tinydrm_spi_transfer(spi, speed_hz, bpw, par, num);
}
/**
diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h
index 10b35375a009..708c5a7d51e0 100644
--- a/include/drm/tinydrm/tinydrm-helpers.h
+++ b/include/drm/tinydrm/tinydrm-helpers.h
@@ -42,7 +42,6 @@ int tinydrm_display_pipe_init(struct drm_device *drm,
unsigned int rotation);
int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
- struct spi_transfer *header, u8 bpw, const void *buf,
- size_t len);
+ u8 bpw, const void *buf, size_t len);
#endif /* __LINUX_TINYDRM_HELPERS_H */