From 8105936684681195d9073880b06a123b2e316811 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean Date: Thu, 26 Sep 2019 13:51:42 +0300 Subject: spi: tegra114: change format for `spi_set_cs_timing()` function The initial version of `spi_set_cs_timing()` was implemented with consideration only for clock-cycles as delay. For cases like `CS setup` time, it's sometimes needed that micro-seconds (or nano-seconds) are required, or sometimes even longer delays, for cases where the device needs a little longer to start transferring that after CS is asserted. Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20190926105147.7839-15-alexandru.ardelean@analog.com Signed-off-by: Mark Brown --- drivers/spi/spi-tegra114.c | 22 ++++++++++++++++++++-- drivers/spi/spi.c | 16 ++++++++++------ include/linux/spi/spi.h | 9 ++++++--- 3 files changed, 36 insertions(+), 11 deletions(-) diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c index 8133dc49d34f..e6a450d9b4f0 100644 --- a/drivers/spi/spi-tegra114.c +++ b/drivers/spi/spi-tegra114.c @@ -723,15 +723,31 @@ static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi, dma_release_channel(dma_chan); } -static void tegra_spi_set_hw_cs_timing(struct spi_device *spi, u8 setup_dly, - u8 hold_dly, u8 inactive_dly) +static int tegra_spi_set_hw_cs_timing(struct spi_device *spi, + struct spi_delay *setup, + struct spi_delay *hold, + struct spi_delay *inactive) { struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master); + u8 setup_dly, hold_dly, inactive_dly; u32 setup_hold; u32 spi_cs_timing; u32 inactive_cycles; u8 cs_state; + if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) || + (hold && hold->unit != SPI_DELAY_UNIT_SCK) || + (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) { + dev_err(&spi->dev, + "Invalid delay unit %d, should be SPI_DELAY_UNIT_SCK\n", + SPI_DELAY_UNIT_SCK); + return -EINVAL; + } + + setup_dly = setup ? setup->value : 0; + hold_dly = hold ? hold->value : 0; + inactive_dly = inactive ? inactive->value : 0; + setup_dly = min_t(u8, setup_dly, MAX_SETUP_HOLD_CYCLES); hold_dly = min_t(u8, hold_dly, MAX_SETUP_HOLD_CYCLES); if (setup_dly && hold_dly) { @@ -758,6 +774,8 @@ static void tegra_spi_set_hw_cs_timing(struct spi_device *spi, u8 setup_dly, tspi->spi_cs_timing2 = spi_cs_timing; tegra_spi_writel(tspi, spi_cs_timing, SPI_CS_TIMING2); } + + return 0; } static u32 tegra_spi_setup_transfer_one(struct spi_device *spi, diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 2e448078a117..6beeb363515c 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -3269,15 +3269,19 @@ EXPORT_SYMBOL_GPL(spi_setup); /** * spi_set_cs_timing - configure CS setup, hold, and inactive delays * @spi: the device that requires specific CS timing configuration - * @setup: CS setup time in terms of clock count - * @hold: CS hold time in terms of clock count - * @inactive_dly: CS inactive delay between transfers in terms of clock count + * @setup: CS setup time specified via @spi_delay + * @hold: CS hold time specified via @spi_delay + * @inactive: CS inactive delay between transfers specified via @spi_delay + * + * Return: zero on success, else a negative error code. */ -void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, - u8 inactive_dly) +int spi_set_cs_timing(struct spi_device *spi, struct spi_delay *setup, + struct spi_delay *hold, struct spi_delay *inactive) { if (spi->controller->set_cs_timing) - spi->controller->set_cs_timing(spi, setup, hold, inactive_dly); + return spi->controller->set_cs_timing(spi, setup, hold, + inactive); + return -ENOTSUPP; } EXPORT_SYMBOL_GPL(spi_set_cs_timing); diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index fe5b85df2c79..f9b4ba2db08d 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -524,8 +524,8 @@ struct spi_controller { * to configure specific CS timing through spi_set_cs_timing() after * spi_setup(). */ - void (*set_cs_timing)(struct spi_device *spi, u8 setup_clk_cycles, - u8 hold_clk_cycles, u8 inactive_clk_cycles); + int (*set_cs_timing)(struct spi_device *spi, struct spi_delay *setup, + struct spi_delay *hold, struct spi_delay *inactive); /* bidirectional bulk transfers * @@ -1068,7 +1068,10 @@ static inline void spi_message_free(struct spi_message *m) kfree(m); } -extern void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, u8 inactive_dly); +extern int spi_set_cs_timing(struct spi_device *spi, + struct spi_delay *setup, + struct spi_delay *hold, + struct spi_delay *inactive); extern int spi_setup(struct spi_device *spi); extern int spi_async(struct spi_device *spi, struct spi_message *message); -- cgit v1.2.3