The patch spi: core,atmel: convert `word_delay_usecs` -> `word_delay` for spi_device has been applied to the spi tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-5.5 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 6c613f68aabf33385c01e949204ac5ed30887161 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> Date: Thu, 26 Sep 2019 13:51:35 +0300 Subject: [PATCH] spi: core,atmel: convert `word_delay_usecs` -> `word_delay` for spi_device This change does a conversion from the `word_delay_usecs` -> `word_delay` for the `spi_device` struct. This allows users to specify inter-word delays in other unit types (nano-seconds or clock cycles), depending on how users want. The Atmel SPI driver is the only current user of the `word_delay_usecs` field (from the `spi_device` struct). So, it needed a slight conversion to use the `word_delay` as an `spi_delay` struct. In SPI core, the only required mechanism is to update the `word_delay` information per `spi_transfer`. This requires a bit more logic than before, because it needs that both delays be converted to a common unit (nano-seconds) for comparison. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> Link: https://lore.kernel.org/r/20190926105147.7839-8-alexandru.ardelean@xxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- drivers/spi/spi-atmel.c | 26 ++++++++++++++++++++++++-- drivers/spi/spi.c | 24 ++++++++++++++++++++++-- include/linux/spi/spi.h | 7 ++----- 3 files changed, 48 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 3ed5e663da6f..1471b049f99a 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -1149,12 +1149,31 @@ atmel_spi_pdc_interrupt(int irq, void *dev_id) return ret; } +static int atmel_word_delay_csr(struct spi_device *spi, struct atmel_spi *as) +{ + struct spi_delay *delay = &spi->word_delay; + u32 value = delay->value; + + switch (delay->unit) { + case SPI_DELAY_UNIT_NSECS: + value /= 1000; + break; + case SPI_DELAY_UNIT_USECS: + break; + default: + return -EINVAL; + } + + return (as->spi_clk / 1000000 * value) >> 5; +} + static int atmel_spi_setup(struct spi_device *spi) { struct atmel_spi *as; struct atmel_spi_device *asd; u32 csr; unsigned int bits = spi->bits_per_word; + int word_delay_csr; as = spi_master_get_devdata(spi->master); @@ -1178,11 +1197,14 @@ static int atmel_spi_setup(struct spi_device *spi) */ csr |= SPI_BF(DLYBS, 0); + word_delay_csr = atmel_word_delay_csr(spi, as); + if (word_delay_csr < 0) + return word_delay_csr; + /* DLYBCT adds delays between words. This is useful for slow devices * that need a bit of time to setup the next transfer. */ - csr |= SPI_BF(DLYBCT, - (as->spi_clk / 1000000 * spi->word_delay_usecs) >> 5); + csr |= SPI_BF(DLYBCT, word_delay_csr); asd = spi->controller_state; if (!asd) { diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index b69c14082c52..307e440dd92d 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -3281,6 +3281,26 @@ void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, } EXPORT_SYMBOL_GPL(spi_set_cs_timing); +static int _spi_xfer_word_delay_update(struct spi_transfer *xfer, + struct spi_device *spi) +{ + int delay1, delay2; + + delay1 = _spi_delay_to_ns(&xfer->word_delay, xfer); + if (delay1 < 0) + return delay1; + + delay2 = _spi_delay_to_ns(&spi->word_delay, xfer); + if (delay2 < 0) + return delay2; + + if (delay1 < delay2) + memcpy(&xfer->word_delay, &spi->word_delay, + sizeof(xfer->word_delay)); + + return 0; +} + static int __spi_validate(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; @@ -3416,8 +3436,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) return -EINVAL; } - if (xfer->word_delay_usecs < spi->word_delay_usecs) - xfer->word_delay_usecs = spi->word_delay_usecs; + if (_spi_xfer_word_delay_update(xfer, spi)) + return -EINVAL; } message->status = -EINPROGRESS; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 6cb67ad53ffa..ebeb272aeb0f 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -139,7 +139,7 @@ extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer); * the spi_master. * @cs_gpiod: gpio descriptor of the chipselect line (optional, NULL when * not using a GPIO line) - * @word_delay_usecs: microsecond delay to be inserted between consecutive + * @word_delay: delay to be inserted between consecutive * words of a transfer * * @statistics: statistics for the spi_device @@ -189,7 +189,7 @@ struct spi_device { const char *driver_override; int cs_gpio; /* LEGACY: chip select gpio */ struct gpio_desc *cs_gpiod; /* chip select gpio desc */ - uint8_t word_delay_usecs; /* inter-word delay */ + struct spi_delay word_delay; /* inter-word delay */ /* the statistics */ struct spi_statistics statistics; @@ -781,8 +781,6 @@ extern void spi_res_release(struct spi_controller *ctlr, * @delay_usecs: microseconds to delay after this transfer before * (optionally) changing the chipselect status, then starting * the next transfer or completing this @spi_message. - * @word_delay_usecs: microseconds to inter word delay after each word size - * (set by bits_per_word) transmission. * @word_delay: inter word delay to be introduced after each word size * (set by bits_per_word) transmission. * @effective_speed_hz: the effective SCK-speed that was used to @@ -897,7 +895,6 @@ struct spi_transfer { #define SPI_NBITS_DUAL 0x02 /* 2bits transfer */ #define SPI_NBITS_QUAD 0x04 /* 4bits transfer */ u8 bits_per_word; - u8 word_delay_usecs; u16 delay_usecs; struct spi_delay cs_change_delay; struct spi_delay word_delay; -- 2.20.1
