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 --- .../gpu/drm/tinydrm/core/tinydrm-helpers.c | 40 ++----------------- drivers/gpu/drm/tinydrm/ili9225.c | 4 +- drivers/gpu/drm/tinydrm/mipi-dbi.c | 4 +- include/drm/tinydrm/tinydrm-helpers.h | 3 +- 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 */