This introduces a command to set parameters for a pwm device. Signed-off-by: Marc Reilly <marc@xxxxxxxxxxxxxxx> --- commands/Kconfig | 12 +++ commands/Makefile | 1 + commands/pwm.c | 199 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 212 insertions(+) create mode 100644 commands/pwm.c diff --git a/commands/Kconfig b/commands/Kconfig index 4d3ff631a8..28f9e46a59 100644 --- a/commands/Kconfig +++ b/commands/Kconfig @@ -1929,6 +1929,18 @@ config CMD_I2C -w use word (16 bit) wide access -v verbose +config CMD_PWM + bool + depends on PWM + prompt "PWM commands: pwm" + help + pwm - set or show pwm state + + Usage: pwm [dDPfwisv] + + Controls the pwm values such as period and duty cycle, or shows + the current values. + config CMD_LED bool depends on LED diff --git a/commands/Makefile b/commands/Makefile index 98625a0373..011ae59427 100644 --- a/commands/Makefile +++ b/commands/Makefile @@ -69,6 +69,7 @@ obj-$(CONFIG_CMD_GPIO) += gpio.o obj-$(CONFIG_CMD_UNCOMPRESS) += uncompress.o obj-$(CONFIG_CMD_I2C) += i2c.o obj-$(CONFIG_CMD_SPI) += spi.o +obj-$(CONFIG_CMD_PWM) += pwm.o obj-$(CONFIG_CMD_MIPI_DBI) += mipi_dbi.o obj-$(CONFIG_CMD_UBI) += ubi.o obj-$(CONFIG_CMD_UBIFORMAT) += ubiformat.o diff --git a/commands/pwm.c b/commands/pwm.c new file mode 100644 index 0000000000..82535d229e --- /dev/null +++ b/commands/pwm.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// SPDX-FileCopyrightText: © 2023 Marc Reilly <marc@xxxxxxxxxxxxxxx> + +/* pwm - pwm commands */ + +#include <common.h> +#include <command.h> +#include <errno.h> +#include <malloc.h> +#include <getopt.h> +#include <pwm.h> + +#define HZ_TO_NANOSECONDS(x) (1000000000UL/(x)) +#define HZ_FROM_NANOSECONDS(x) (1000000000UL/(x)) + +static bool is_equal_state(struct pwm_state *state1, struct pwm_state *state2) +{ + return (state1->period_ns == state2->period_ns) + && (state1->duty_ns == state2->duty_ns) + && (state1->polarity == state2->polarity) + && (state1->p_enable == state2->p_enable); +} + +static int do_pwm_cmd(int argc, char *argv[]) +{ + struct pwm_device *pwm = NULL; + struct pwm_state state, orig_state; + int error = 0; + char *devname = NULL; + int duty = -1, period = -1; + int freq = -1, width = -1; + bool invert_polarity = false, stop = false; + bool use_default_width = false; + bool verbose = false; + int opt; + + while ((opt = getopt(argc, argv, "d:D:P:f:w:F:isv")) > 0) { + switch (opt) { + case 'd': + devname = optarg; + break; + case 'D': + duty = simple_strtol(optarg, NULL, 0); + break; + case 'P': + period = simple_strtol(optarg, NULL, 0); + break; + case 'F': + /* convenience option for changing frequency without + * having to specify duty width */ + use_default_width = true; + /* fallthrough */ + case 'f': + freq = simple_strtol(optarg, NULL, 0); + break; + case 'w': + width = simple_strtol(optarg, NULL, 0); + break; + case 'i': + invert_polarity = true; + break; + case 's': + stop = true; + break; + case 'v': + verbose = true; + break; + } + } + + if (!devname) { + printf(" need to specify a device\n"); + return COMMAND_ERROR_USAGE; + } + if ((freq == 0) || (period == 0)) { + printf(" period or freqency needs to be non-zero\n"); + return COMMAND_ERROR_USAGE; + } + if (freq >= 0 && period >= 0) { + printf(" specify period or frequency, not both\n"); + return COMMAND_ERROR_USAGE; + } + if (duty >= 0 && width >= 0) { + printf(" specify duty or width, not both\n"); + return COMMAND_ERROR_USAGE; + } + if (width > 100) { + printf(" width (%% duty cycle) can't be more than 100%%\n"); + return COMMAND_ERROR_USAGE; + } + + pwm = pwm_request(devname); + if (!pwm) { + printf(" pwm device %s not found\n", devname); + return -ENODEV; + } + + pwm_get_state(pwm, &state); + + /* argc will be at least 3 with a valid devname */ + if (verbose || (argc <= 3)) { + printf("pwm params for '%s':\n", devname); + printf(" period : %u (ns)\n", state.period_ns); + printf(" duty : %u (ns)\n", state.duty_ns); + printf(" enabled : %d\n", state.p_enable); + printf(" polarity : %s\n", state.polarity == 0 ? "Normal" : "Inverted"); + printf(" freq : %lu (Hz)\n", HZ_FROM_NANOSECONDS(state.period_ns)); + + pwm_free(pwm); + return 0; + } + + if ((state.period_ns == 0) && (freq < 0) && (period < 0)) { + printf(" need to know some timing info: freq or period\n"); + pwm_free(pwm); + return COMMAND_ERROR_USAGE; + } + + orig_state = state; + + if (invert_polarity) + state.polarity = invert_polarity; + + /* period */ + if (freq > 0) { + state.p_enable = true; + state.period_ns = HZ_TO_NANOSECONDS(freq); + if (use_default_width && (width < 0)) { + width = 50; + } + } else if (period > 0) { + state.p_enable = true; + state.period_ns = period; + } + + /* duty */ + if (width >= 0) { + pwm_set_relative_duty_cycle(&state, width, 100); + } else if (duty >= 0) { + state.duty_ns = duty; + } + + if (state.duty_ns > state.period_ns) { + printf(" duty_ns must not be greater than period_ns\n"); + } + + /* only set the state if its changed */ + if (!is_equal_state(&orig_state, & state)) + error = pwm_apply_state(pwm, &state); + + if (error < 0) + printf(" error while applying state: %d\n", error); + + /* stop handled as an additional step on purpose, allows turning off + * output (eg if duty => 0) and stopping in one command + */ + if (stop > 0) { + state.p_enable = false; + error = pwm_apply_state(pwm, &state); + if (error < 0) + printf(" error while stopping: %d\n", error); + } + + pwm_free(pwm); + + return error; +} + +BAREBOX_CMD_HELP_START(pwm) +BAREBOX_CMD_HELP_TEXT("Sets pwm device parameters, or shows current value.") +BAREBOX_CMD_HELP_TEXT(" Specify the pwm device by device name.") +BAREBOX_CMD_HELP_TEXT(" If no other parameters are given, or if args has '-v',") +BAREBOX_CMD_HELP_TEXT(" then show the current values only.") +BAREBOX_CMD_HELP_TEXT(" Timings can either be specified via period + duty (on) duration,") +BAREBOX_CMD_HELP_TEXT(" or via frequency. Duty can be given either as a percentage or time.") +BAREBOX_CMD_HELP_TEXT(" If a parameter is not specified, the current value will be used") +BAREBOX_CMD_HELP_TEXT(" where possible.") +BAREBOX_CMD_HELP_TEXT(" To set an output to inactive state, set the duty to 0.") +BAREBOX_CMD_HELP_TEXT(" (although note this will not by itself stop the pwm running.)") +BAREBOX_CMD_HELP_TEXT(" Stopping the pwm device does not necessarily set the output to inactive,") +BAREBOX_CMD_HELP_TEXT(" but stop is handled last, so can be done in addition to other changes.") +BAREBOX_CMD_HELP_TEXT("Options:") +BAREBOX_CMD_HELP_OPT("-d string", "device name (eg 'pwm0')") +BAREBOX_CMD_HELP_OPT("-D number", "duty cycle (ns)") +BAREBOX_CMD_HELP_OPT("-P number", "period (ns)") +BAREBOX_CMD_HELP_OPT("-f number", "frequency (Hz)") +BAREBOX_CMD_HELP_OPT("-w number", "duty cycle (%) - the on 'width' of each cycle") +BAREBOX_CMD_HELP_OPT("-i\t", "line inverted polarity") +BAREBOX_CMD_HELP_OPT("-s\t", "stop (disable) the pwm device") +BAREBOX_CMD_HELP_OPT("-v\t", "print current values") +BAREBOX_CMD_HELP_END + +BAREBOX_CMD_START(pwm) + .cmd = do_pwm_cmd, + BAREBOX_CMD_DESC("pwm") + BAREBOX_CMD_OPTS("[-dDPfwisv]") + BAREBOX_CMD_GROUP(CMD_GRP_HWMANIP) + BAREBOX_CMD_HELP(cmd_pwm_help) +BAREBOX_CMD_END -- 2.35.3