From a45baa079e2a6b7a5516354c6ff08702232384f5 Mon Sep 17 00:00:00 2001 From: Boerge Struempfel Date: Tue, 30 May 2023 16:16:37 +0200 Subject: [PATCH 1/5] spi: add SPI_MOSI_IDLE_LOW mode bit Some spi controller switch the mosi line to high, whenever they are idle. This may not be desired in all use cases. For example neopixel leds can get confused and flicker due to misinterpreting the idle state. Therefore, we introduce a new spi-mode bit, with which the idle behaviour can be overwritten on a per device basis. Signed-off-by: Boerge Struempfel Link: https://lore.kernel.org/r/20230530141641.1155691-2-boerge.struempfel@gmail.com Signed-off-by: Mark Brown --- include/uapi/linux/spi/spi.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/spi/spi.h b/include/uapi/linux/spi/spi.h index 9d5f58059703..ca56e477d161 100644 --- a/include/uapi/linux/spi/spi.h +++ b/include/uapi/linux/spi/spi.h @@ -28,6 +28,7 @@ #define SPI_RX_OCTAL _BITUL(14) /* receive with 8 wires */ #define SPI_3WIRE_HIZ _BITUL(15) /* high impedance turnaround */ #define SPI_RX_CPHA_FLIP _BITUL(16) /* flip CPHA on Rx only xfer */ +#define SPI_MOSI_IDLE_LOW _BITUL(17) /* leave mosi line low when idle */ /* * All the bits defined above should be covered by SPI_MODE_USER_MASK. @@ -37,6 +38,6 @@ * These bits must not overlap. A static assert check should make sure of that. * If adding extra bits, make sure to increase the bit index below as well. */ -#define SPI_MODE_USER_MASK (_BITUL(17) - 1) +#define SPI_MODE_USER_MASK (_BITUL(18) - 1) #endif /* _UAPI_SPI_H */ From 6a983ff5102ff0d859df05ca3f5cf2f6a17c0fad Mon Sep 17 00:00:00 2001 From: Boerge Struempfel Date: Tue, 30 May 2023 16:16:38 +0200 Subject: [PATCH 2/5] spi: spi-imx: add support for SPI_MOSI_IDLE_LOW mode bit By default, the spi-imx controller pulls the mosi line high, whenever it is idle. This behaviour can be inverted per CS by setting the corresponding DATA_CTL bit in the config register of the controller. Also, since the controller mode-bits have to be touched anyways, the SPI_CPOL and SPI_CPHA are replaced by the combined SPI_MODE_X_MASK flag. Signed-off-by: Boerge Struempfel Link: https://lore.kernel.org/r/20230530141641.1155691-3-boerge.struempfel@gmail.com Signed-off-by: Mark Brown --- drivers/spi/spi-imx.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index bd6ddb142b13..6f4d3cb81fdf 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -281,6 +281,7 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4)) #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8)) #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12)) +#define MX51_ECSPI_CONFIG_DATACTL(cs) (1 << ((cs & 3) + 16)) #define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20)) #define MX51_ECSPI_INT 0x10 @@ -573,6 +574,11 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx, cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi_get_chipselect(spi, 0)); } + if (spi->mode & SPI_MOSI_IDLE_LOW) + cfg |= MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0)); + else + cfg &= ~MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0)); + if (spi->mode & SPI_CS_HIGH) cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi_get_chipselect(spi, 0)); else @@ -1743,7 +1749,8 @@ static int spi_imx_probe(struct platform_device *pdev) controller->prepare_message = spi_imx_prepare_message; controller->unprepare_message = spi_imx_unprepare_message; controller->slave_abort = spi_imx_slave_abort; - controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS; + controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS | + SPI_MOSI_IDLE_LOW; if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx)) From 5cc223ca4858ec40bd2b8522ebc51c0d4963e51f Mon Sep 17 00:00:00 2001 From: Boerge Struempfel Date: Tue, 30 May 2023 16:16:39 +0200 Subject: [PATCH 3/5] spi: spidev: add two new spi mode bits Allow userspace to set SPI_MOSI_IDLE_LOW and the SPI_3WIRE_HIZ mode bit using the SPI_IOC_WR_MODE32 ioctl. Signed-off-by: Boerge Struempfel Link: https://lore.kernel.org/r/20230530141641.1155691-4-boerge.struempfel@gmail.com Signed-off-by: Mark Brown --- drivers/spi/spidev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 39d94c850839..c8b938e0f342 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -64,7 +64,8 @@ static_assert(N_SPI_MINORS > 0 && N_SPI_MINORS <= 256); | SPI_NO_CS | SPI_READY | SPI_TX_DUAL \ | SPI_TX_QUAD | SPI_TX_OCTAL | SPI_RX_DUAL \ | SPI_RX_QUAD | SPI_RX_OCTAL \ - | SPI_RX_CPHA_FLIP) + | SPI_RX_CPHA_FLIP | SPI_3WIRE_HIZ \ + | SPI_MOSI_IDLE_LOW) struct spidev_data { dev_t devt; From 113f36f2dce3a5a1aacbfa700c44080ec37ee3a0 Mon Sep 17 00:00:00 2001 From: Boerge Struempfel Date: Tue, 30 May 2023 16:16:40 +0200 Subject: [PATCH 4/5] spi: spidev_test: Sorted the options into logical groups In order to increase usability, the command line options are sorted into logical groups. In addition, the usage string was sorted alphabetically, and the missing parameters '8','i' and 'o' were added. Furthermore, the option descriptions were moved further to the right, in order to allow for longer option names. Signed-off-by: Boerge Struempfel Link: https://lore.kernel.org/r/20230530141641.1155691-5-boerge.struempfel@gmail.com Signed-off-by: Mark Brown --- tools/spi/spidev_test.c | 90 ++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 42 deletions(-) diff --git a/tools/spi/spidev_test.c b/tools/spi/spidev_test.c index b0ca44c70e83..2d2cee339b39 100644 --- a/tools/spi/spidev_test.c +++ b/tools/spi/spidev_test.c @@ -172,28 +172,34 @@ static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len) static void print_usage(const char *prog) { - printf("Usage: %s [-DsbdlHOLC3vpNR24SI]\n", prog); - puts(" -D --device device to use (default /dev/spidev1.1)\n" - " -s --speed max speed (Hz)\n" - " -d --delay delay (usec)\n" - " -b --bpw bits per word\n" - " -i --input input data from a file (e.g. \"test.bin\")\n" - " -o --output output data to a file (e.g. \"results.bin\")\n" - " -l --loop loopback\n" - " -H --cpha clock phase\n" - " -O --cpol clock polarity\n" - " -L --lsb least significant bit first\n" - " -C --cs-high chip select active high\n" - " -3 --3wire SI/SO signals shared\n" - " -v --verbose Verbose (show tx buffer)\n" - " -p Send data (e.g. \"1234\\xde\\xad\")\n" - " -N --no-cs no chip select\n" - " -R --ready slave pulls low to pause\n" - " -2 --dual dual transfer\n" - " -4 --quad quad transfer\n" - " -8 --octal octal transfer\n" - " -S --size transfer size\n" - " -I --iter iterations\n"); + printf("Usage: %s [-2348CDHILNORSbdilopsv]\n", prog); + puts("general device settings:\n" + " -D --device device to use (default /dev/spidev1.1)\n" + " -s --speed max speed (Hz)\n" + " -d --delay delay (usec)\n" + " -l --loop loopback\n" + "spi mode:\n" + " -H --cpha clock phase\n" + " -O --cpol clock polarity\n" + "number of wires for transmission:\n" + " -2 --dual dual transfer\n" + " -4 --quad quad transfer\n" + " -8 --octal octal transfer\n" + " -3 --3wire SI/SO signals shared\n" + "data:\n" + " -i --input input data from a file (e.g. \"test.bin\")\n" + " -o --output output data to a file (e.g. \"results.bin\")\n" + " -p Send data (e.g. \"1234\\xde\\xad\")\n" + " -S --size transfer size\n" + " -I --iter iterations\n" + "additional parameters:\n" + " -b --bpw bits per word\n" + " -L --lsb least significant bit first\n" + " -C --cs-high chip select active high\n" + " -N --no-cs no chip select\n" + " -R --ready slave pulls low to pause\n" + "misc:\n" + " -v --verbose Verbose (show tx buffer)\n"); exit(1); } @@ -201,26 +207,26 @@ static void parse_opts(int argc, char *argv[]) { while (1) { static const struct option lopts[] = { - { "device", 1, 0, 'D' }, - { "speed", 1, 0, 's' }, - { "delay", 1, 0, 'd' }, - { "bpw", 1, 0, 'b' }, - { "input", 1, 0, 'i' }, - { "output", 1, 0, 'o' }, - { "loop", 0, 0, 'l' }, - { "cpha", 0, 0, 'H' }, - { "cpol", 0, 0, 'O' }, - { "lsb", 0, 0, 'L' }, - { "cs-high", 0, 0, 'C' }, - { "3wire", 0, 0, '3' }, - { "no-cs", 0, 0, 'N' }, - { "ready", 0, 0, 'R' }, - { "dual", 0, 0, '2' }, - { "verbose", 0, 0, 'v' }, - { "quad", 0, 0, '4' }, - { "octal", 0, 0, '8' }, - { "size", 1, 0, 'S' }, - { "iter", 1, 0, 'I' }, + { "device", 1, 0, 'D' }, + { "speed", 1, 0, 's' }, + { "delay", 1, 0, 'd' }, + { "loop", 0, 0, 'l' }, + { "cpha", 0, 0, 'H' }, + { "cpol", 0, 0, 'O' }, + { "dual", 0, 0, '2' }, + { "quad", 0, 0, '4' }, + { "octal", 0, 0, '8' }, + { "3wire", 0, 0, '3' }, + { "input", 1, 0, 'i' }, + { "output", 1, 0, 'o' }, + { "size", 1, 0, 'S' }, + { "iter", 1, 0, 'I' }, + { "bpw", 1, 0, 'b' }, + { "lsb", 0, 0, 'L' }, + { "cs-high", 0, 0, 'C' }, + { "no-cs", 0, 0, 'N' }, + { "ready", 0, 0, 'R' }, + { "verbose", 0, 0, 'v' }, { NULL, 0, 0, 0 }, }; int c; From b229a7f530ebea90c8e21b56872f3102e3d54461 Mon Sep 17 00:00:00 2001 From: Boerge Struempfel Date: Tue, 30 May 2023 16:16:41 +0200 Subject: [PATCH 5/5] spi: spidev_test Add three missing spi mode bits Added the three missing spi mode bits SPI_3WIRE_HIZ, SPI_RX_CPHA_FLIP, and SPI_MOSI_IDLE_LOW. Signed-off-by: Boerge Struempfel Link: https://lore.kernel.org/r/20230530141641.1155691-6-boerge.struempfel@gmail.com Signed-off-by: Mark Brown --- tools/spi/spidev_test.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/tools/spi/spidev_test.c b/tools/spi/spidev_test.c index 2d2cee339b39..9179942d7f15 100644 --- a/tools/spi/spidev_test.c +++ b/tools/spi/spidev_test.c @@ -172,7 +172,7 @@ static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len) static void print_usage(const char *prog) { - printf("Usage: %s [-2348CDHILNORSbdilopsv]\n", prog); + printf("Usage: %s [-2348CDFHILMNORSZbdilopsv]\n", prog); puts("general device settings:\n" " -D --device device to use (default /dev/spidev1.1)\n" " -s --speed max speed (Hz)\n" @@ -181,11 +181,13 @@ static void print_usage(const char *prog) "spi mode:\n" " -H --cpha clock phase\n" " -O --cpol clock polarity\n" + " -F --rx-cpha-flip flip CPHA on Rx only xfer\n" "number of wires for transmission:\n" " -2 --dual dual transfer\n" " -4 --quad quad transfer\n" " -8 --octal octal transfer\n" " -3 --3wire SI/SO signals shared\n" + " -Z --3wire-hiz high impedance turnaround\n" "data:\n" " -i --input input data from a file (e.g. \"test.bin\")\n" " -o --output output data to a file (e.g. \"results.bin\")\n" @@ -198,6 +200,7 @@ static void print_usage(const char *prog) " -C --cs-high chip select active high\n" " -N --no-cs no chip select\n" " -R --ready slave pulls low to pause\n" + " -M --mosi-idle-low leave mosi line low when idle\n" "misc:\n" " -v --verbose Verbose (show tx buffer)\n"); exit(1); @@ -213,10 +216,12 @@ static void parse_opts(int argc, char *argv[]) { "loop", 0, 0, 'l' }, { "cpha", 0, 0, 'H' }, { "cpol", 0, 0, 'O' }, + { "rx-cpha-flip", 0, 0, 'F' }, { "dual", 0, 0, '2' }, { "quad", 0, 0, '4' }, { "octal", 0, 0, '8' }, { "3wire", 0, 0, '3' }, + { "3wire-hiz", 0, 0, 'Z' }, { "input", 1, 0, 'i' }, { "output", 1, 0, 'o' }, { "size", 1, 0, 'S' }, @@ -226,12 +231,13 @@ static void parse_opts(int argc, char *argv[]) { "cs-high", 0, 0, 'C' }, { "no-cs", 0, 0, 'N' }, { "ready", 0, 0, 'R' }, + { "mosi-idle-low", 0, 0, 'M' }, { "verbose", 0, 0, 'v' }, { NULL, 0, 0, 0 }, }; int c; - c = getopt_long(argc, argv, "D:s:d:b:i:o:lHOLC3NR248p:vS:I:", + c = getopt_long(argc, argv, "D:s:d:b:i:o:lHOLC3ZFMNR248p:vS:I:", lopts, NULL); if (c == -1) @@ -274,6 +280,15 @@ static void parse_opts(int argc, char *argv[]) case '3': mode |= SPI_3WIRE; break; + case 'Z': + mode |= SPI_3WIRE_HIZ; + break; + case 'F': + mode |= SPI_RX_CPHA_FLIP; + break; + case 'M': + mode |= SPI_MOSI_IDLE_LOW; + break; case 'N': mode |= SPI_NO_CS; break;