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authorAtsushi Nemoto <atsushi.nemoto@sord.co.jp>2022-05-19 02:46:04 +0300
committerMark Brown <broonie@kernel.org>2022-06-06 14:41:36 +0300
commit8d0b512844fdee83b6299647aa178828a4ebfc3b (patch)
tree14972e0e17ca64aa4dc3a042c654a1f7a33f753f /drivers/spi/spi-ti-qspi.c
parent6598b91b5ac32bc756d7c3000a31f775d4ead1c4 (diff)
downloadlinux-8d0b512844fdee83b6299647aa178828a4ebfc3b.tar.xz
spi: spi-ti-qspi: Support per-transfer and per-slave speed_hz settings
The spi-ti-qspi driver initializes its spi clock by the spi-max-frequency property from the controller node, and ignores per-transfer (and per-slave) speed_hz settings. Isolate clock settings out from ti_qspi_setup() and call it from ti_qspi_start_transfer_one() and ti_qspi_exec_mem_op(), using per-transfer speed_hz and per-slave max_speed_hz settings. Also drop spi_max_frequency from struct ti_qspi and use spi_master's max_speed_hz. Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp> Link: https://lore.kernel.org/r/20220519.084604.966119051165023533.atsushi.nemoto@sord.co.jp Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-ti-qspi.c')
-rw-r--r--drivers/spi/spi-ti-qspi.c75
1 files changed, 39 insertions, 36 deletions
diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index b5b65d882d7a..60086869bcae 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -57,7 +57,6 @@ struct ti_qspi {
void *rx_bb_addr;
struct dma_chan *rx_chan;
- u32 spi_max_frequency;
u32 cmd;
u32 dc;
@@ -140,37 +139,19 @@ static inline void ti_qspi_write(struct ti_qspi *qspi,
static int ti_qspi_setup(struct spi_device *spi)
{
struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
- struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
- int clk_div = 0, ret;
- u32 clk_ctrl_reg, clk_rate, clk_mask;
+ int ret;
if (spi->master->busy) {
dev_dbg(qspi->dev, "master busy doing other transfers\n");
return -EBUSY;
}
- if (!qspi->spi_max_frequency) {
+ if (!qspi->master->max_speed_hz) {
dev_err(qspi->dev, "spi max frequency not defined\n");
return -EINVAL;
}
- clk_rate = clk_get_rate(qspi->fclk);
-
- clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
-
- if (clk_div < 0) {
- dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
- return -EINVAL;
- }
-
- if (clk_div > QSPI_CLK_DIV_MAX) {
- dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
- QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
- return -EINVAL;
- }
-
- dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
- qspi->spi_max_frequency, clk_div);
+ spi->max_speed_hz = min(spi->max_speed_hz, qspi->master->max_speed_hz);
ret = pm_runtime_resume_and_get(qspi->dev);
if (ret < 0) {
@@ -178,18 +159,6 @@ static int ti_qspi_setup(struct spi_device *spi)
return ret;
}
- clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
-
- clk_ctrl_reg &= ~QSPI_CLK_EN;
-
- /* disable SCLK */
- ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
-
- /* enable SCLK */
- clk_mask = QSPI_CLK_EN | clk_div;
- ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
- ctx_reg->clkctrl = clk_mask;
-
pm_runtime_mark_last_busy(qspi->dev);
ret = pm_runtime_put_autosuspend(qspi->dev);
if (ret < 0) {
@@ -200,6 +169,37 @@ static int ti_qspi_setup(struct spi_device *spi)
return 0;
}
+static void ti_qspi_setup_clk(struct ti_qspi *qspi, u32 speed_hz)
+{
+ struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
+ int clk_div;
+ u32 clk_ctrl_reg, clk_rate, clk_ctrl_new;
+
+ clk_rate = clk_get_rate(qspi->fclk);
+ clk_div = DIV_ROUND_UP(clk_rate, speed_hz) - 1;
+ clk_div = clamp(clk_div, 0, QSPI_CLK_DIV_MAX);
+ dev_dbg(qspi->dev, "hz: %d, clock divider %d\n", speed_hz, clk_div);
+
+ pm_runtime_resume_and_get(qspi->dev);
+
+ clk_ctrl_new = QSPI_CLK_EN | clk_div;
+ if (ctx_reg->clkctrl != clk_ctrl_new) {
+ clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ clk_ctrl_reg &= ~QSPI_CLK_EN;
+
+ /* disable SCLK */
+ ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
+
+ /* enable SCLK */
+ ti_qspi_write(qspi, clk_ctrl_new, QSPI_SPI_CLOCK_CNTRL_REG);
+ ctx_reg->clkctrl = clk_ctrl_new;
+ }
+
+ pm_runtime_mark_last_busy(qspi->dev);
+ pm_runtime_put_autosuspend(qspi->dev);
+}
+
static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
{
struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
@@ -623,8 +623,10 @@ static int ti_qspi_exec_mem_op(struct spi_mem *mem,
mutex_lock(&qspi->list_lock);
- if (!qspi->mmap_enabled || qspi->current_cs != mem->spi->chip_select)
+ if (!qspi->mmap_enabled || qspi->current_cs != mem->spi->chip_select) {
+ ti_qspi_setup_clk(qspi, mem->spi->max_speed_hz);
ti_qspi_enable_memory_map(mem->spi);
+ }
ti_qspi_setup_mmap_read(mem->spi, op->cmd.opcode, op->data.buswidth,
op->addr.nbytes, op->dummy.nbytes);
@@ -701,6 +703,7 @@ static int ti_qspi_start_transfer_one(struct spi_master *master,
wlen = t->bits_per_word >> 3;
transfer_len_words = min(t->len / wlen, frame_len_words);
+ ti_qspi_setup_clk(qspi, t->speed_hz);
ret = qspi_transfer_msg(qspi, t, transfer_len_words * wlen);
if (ret) {
dev_dbg(qspi->dev, "transfer message failed\n");
@@ -851,7 +854,7 @@ static int ti_qspi_probe(struct platform_device *pdev)
pm_runtime_enable(&pdev->dev);
if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
- qspi->spi_max_frequency = max_freq;
+ master->max_speed_hz = max_freq;
dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, mask);