Den 10.03.2018 16.52, skrev Meghana Madhyastha:
Remove chunk splitting in tinydrm_spi_transfer in tinydrm-helpers as the spi core will split a buffer into max_dma_len chunks for the spi controller driver to handle, automatic byte swapping in tinydrm_spi_transfer as it doesn't have users.
Signed-off-by: Meghana Madhyastha meghana.madhyastha@gmail.com
drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 48 ++++---------------------- drivers/gpu/drm/tinydrm/mipi-dbi.c | 10 ++---- drivers/spi/spi-bcm2835.c | 2 +- 3 files changed, 9 insertions(+), 51 deletions(-)
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c index bf96072d1b97..6064099e8e63 100644 --- a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c +++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c @@ -452,62 +452,26 @@ int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz, struct spi_transfer tr = { .bits_per_word = bpw, .speed_hz = speed_hz,
.tx_buf = buf,.len = len
u16 *swap_buf = NULL; size_t max_chunk;
size_t chunk;
int ret = 0;
if (WARN_ON_ONCE(bpw != 8 && bpw != 16))
return -EINVAL;max_chunk = tinydrm_spi_max_transfer_size(spi, 0);
- max_chunk = SIZE_MAX;
max_chunk isn't used so can be removed. tinydrm_spi_max_transfer_size() can also be remove now.
if (drm_debug & DRM_UT_DRIVER) pr_debug("[drm:%s] bpw=%u, max_chunk=%zu, transfers:\n",
__func__, bpw, max_chunk);- if (bpw == 16 && !tinydrm_spi_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;}- }
__func__, bpw, max_chunk);spi_message_init(&m); if (header) spi_message_add_tail(header, &m); spi_message_add_tail(&tr, &m);
- 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;tinydrm_dbg_spi_message(spi, &m);ret = spi_sync(spi, &m);if (ret)return ret;- }
- tinydrm_dbg_spi_message(spi, &m);
- return 0;
- return spi_sync(spi, &m); } EXPORT_SYMBOL(tinydrm_spi_transfer);
diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c index 75dd65c57e74..c8af2d65c2ad 100644 --- a/drivers/gpu/drm/tinydrm/mipi-dbi.c +++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c @@ -886,15 +886,9 @@ static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 cmd, int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi, struct gpio_desc *dc) {
size_t tx_size = tinydrm_spi_max_transfer_size(spi, 0); struct device *dev = &spi->dev; int ret;
if (tx_size < 16) {
DRM_ERROR("SPI transmit buffer too small: %zu\n", tx_size);return -EINVAL;}
/*
- Even though it's not the SPI device that does DMA (the master does),
- the dma mask is necessary for the dma_alloc_wc() in
@@ -924,8 +918,8 @@ int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi, mipi->swap_bytes = true; } else { mipi->command = mipi_dbi_typec1_command;
mipi->tx_buf9_len = tx_size;mipi->tx_buf9 = devm_kmalloc(dev, tx_size, GFP_KERNEL);
mipi->tx_buf9_len = SZ_16K;mipi->tx_buf9 = devm_kmalloc(dev, mipi->tx_buf9_len, GFP_KERNEL);diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 0dcc45f158b8..2fd650891c07 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -448,7 +448,7 @@ static void bcm2835_dma_init(struct spi_master *master, struct device *dev)
/* all went well, so set can_dma */ master->can_dma = bcm2835_spi_can_dma;
- master->max_dma_len = 65535; /* limitation by BCM2835_SPI_DLEN */
- master->max_dma_len = 65528; /* limitation by BCM2835_SPI_DLEN */
This change belongs in the spi-bcm2835 patch. You need to tell us why the change is needed.
Noralf.
/* need to do TX AND RX DMA, so we need dummy buffers */ master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;