* [PATCH v11 0/3] PPS: pps-gpio PPS ECHO implementation @ 2018-11-29 0:26 Tom Burkart 2018-11-29 0:26 ` [PATCH v11 1/3] pps: descriptor-based gpio Tom Burkart 0 siblings, 1 reply; 4+ messages in thread From: Tom Burkart @ 2018-11-29 0:26 UTC (permalink / raw) To: Linux kernel mailing list; +Cc: Tom Burkart Hi all, please find attached the PPS-GPIO PPS ECHO implementation patch. The driver claims to have echo functionality in the sysfs interface but this functionality is not present. This patch provides this functionality. Part 1 of the patch change the original driver from the number based GPIO ABI to the descriptor based ABI. Parts 2 and 3 then add the PPS ECHO functionality. This is enabled if a "echo-gpios" entry is found in the devicetree. Changes in v8: Changes requested by Rob Herring and Philipp Zabel: DT explanation and don't change the DT entry for the PPS gpio. Changes in v9: Simplify "if" expression by doing echo_active_ms validation earlier. Changes in v10: Changes requested by Philipp Zabel: Mostly cosmetic changes: PATCH 2/4 now reviewed. Thanks a lot, Philipp! (Please note that as of v11 PATCH 1 is gone so this has become PATCH 1) Changes in v11: Changes requested by Rob Herring: All changes in regard to the capture-clear DT entry are gone. On the linuxpps mailing list it was suggested to use a hrtimer for resetting the GPIO ECHO active state to the inactive state. Please also comment on whether a hrtimer is necessary/desirable for the purpose of resetting the echo pin active state. I am happy to implement it if this is useful/desirable. Please install, test and comment as it is now a quite major change to the driver. Suggestions for improvement are welcome. Tom Burkart Tom Burkart (3): pps: descriptor-based gpio dt-bindings: pps: pps-gpio PPS ECHO implementation pps: pps-gpio pps-echo implementation Documentation/devicetree/bindings/pps/pps-gpio.txt | 9 ++ drivers/pps/clients/pps-gpio.c | 167 ++++++++++++++++----- include/linux/pps-gpio.h | 6 +- 3 files changed, 142 insertions(+), 40 deletions(-) -- 2.12.3 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v11 1/3] pps: descriptor-based gpio 2018-11-29 0:26 [PATCH v11 0/3] PPS: pps-gpio PPS ECHO implementation Tom Burkart @ 2018-11-29 0:26 ` Tom Burkart 2018-11-29 0:26 ` [PATCH v11 2/3] dt-bindings: pps: pps-gpio PPS ECHO implementation Tom Burkart 0 siblings, 1 reply; 4+ messages in thread From: Tom Burkart @ 2018-11-29 0:26 UTC (permalink / raw) To: Linux kernel mailing list; +Cc: Tom Burkart This patch changes the GPIO access for the pps-gpio driver from the integer based ABI to the descriptor based ABI. Reviewed-by: Philipp Zabel <philipp.zabel@gmail.com> Signed-off-by: Tom Burkart <tom@aussec.com> --- drivers/pps/clients/pps-gpio.c | 67 +++++++++++++++++++----------------------- include/linux/pps-gpio.h | 3 +- 2 files changed, 32 insertions(+), 38 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index 333ad7d5b45b..5d764dceabc5 100644 --- a/drivers/pps/clients/pps-gpio.c +++ b/drivers/pps/clients/pps-gpio.c @@ -31,7 +31,7 @@ #include <linux/slab.h> #include <linux/pps_kernel.h> #include <linux/pps-gpio.h> -#include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/list.h> #include <linux/of_device.h> #include <linux/of_gpio.h> @@ -41,9 +41,9 @@ struct pps_gpio_device_data { int irq; /* IRQ used as PPS source */ struct pps_device *pps; /* PPS source device */ struct pps_source_info info; /* PPS source information */ + struct gpio_desc *gpio_pin; /* GPIO port descriptors */ bool assert_falling_edge; bool capture_clear; - unsigned int gpio_pin; }; /* @@ -61,18 +61,37 @@ static irqreturn_t pps_gpio_irq_handler(int irq, void *data) info = data; - rising_edge = gpio_get_value(info->gpio_pin); + rising_edge = gpiod_get_value(info->gpio_pin); if ((rising_edge && !info->assert_falling_edge) || (!rising_edge && info->assert_falling_edge)) pps_event(info->pps, &ts, PPS_CAPTUREASSERT, NULL); else if (info->capture_clear && ((rising_edge && info->assert_falling_edge) || - (!rising_edge && !info->assert_falling_edge))) + (!rising_edge && !info->assert_falling_edge))) pps_event(info->pps, &ts, PPS_CAPTURECLEAR, NULL); return IRQ_HANDLED; } +static int pps_gpio_setup(struct platform_device *pdev) +{ + struct pps_gpio_device_data *data = platform_get_drvdata(pdev); + struct device_node *np = pdev->dev.of_node; + + data->gpio_pin = devm_gpiod_get(&pdev->dev, + NULL, /* request "gpios" */ + GPIOD_IN); + if (IS_ERR(data->gpio_pin)) { + dev_err(&pdev->dev, + "failed to request PPS GPIO\n"); + return PTR_ERR(data->gpio_pin); + } + + if (of_property_read_bool(np, "assert-falling-edge")) + data->assert_falling_edge = true; + return 0; +} + static unsigned long get_irqf_trigger_flags(const struct pps_gpio_device_data *data) { @@ -90,53 +109,30 @@ get_irqf_trigger_flags(const struct pps_gpio_device_data *data) static int pps_gpio_probe(struct platform_device *pdev) { struct pps_gpio_device_data *data; - const char *gpio_label; int ret; int pps_default_params; const struct pps_gpio_platform_data *pdata = pdev->dev.platform_data; - struct device_node *np = pdev->dev.of_node; /* allocate space for device info */ - data = devm_kzalloc(&pdev->dev, sizeof(struct pps_gpio_device_data), - GFP_KERNEL); + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; + platform_set_drvdata(pdev, data); + /* GPIO setup */ if (pdata) { data->gpio_pin = pdata->gpio_pin; - gpio_label = pdata->gpio_label; data->assert_falling_edge = pdata->assert_falling_edge; data->capture_clear = pdata->capture_clear; } else { - ret = of_get_gpio(np, 0); - if (ret < 0) { - dev_err(&pdev->dev, "failed to get GPIO from device tree\n"); - return ret; - } - data->gpio_pin = ret; - gpio_label = PPS_GPIO_NAME; - - if (of_get_property(np, "assert-falling-edge", NULL)) - data->assert_falling_edge = true; - } - - /* GPIO setup */ - ret = devm_gpio_request(&pdev->dev, data->gpio_pin, gpio_label); - if (ret) { - dev_err(&pdev->dev, "failed to request GPIO %u\n", - data->gpio_pin); - return ret; - } - - ret = gpio_direction_input(data->gpio_pin); - if (ret) { - dev_err(&pdev->dev, "failed to set pin direction\n"); - return -EINVAL; + ret = pps_gpio_setup(pdev); + if (ret) + return -EINVAL; } /* IRQ setup */ - ret = gpio_to_irq(data->gpio_pin); + ret = gpiod_to_irq(data->gpio_pin); if (ret < 0) { dev_err(&pdev->dev, "failed to map GPIO to IRQ: %d\n", ret); return -EINVAL; @@ -173,7 +169,6 @@ static int pps_gpio_probe(struct platform_device *pdev) return -EINVAL; } - platform_set_drvdata(pdev, data); dev_info(data->pps->dev, "Registered IRQ %d as PPS source\n", data->irq); @@ -209,4 +204,4 @@ MODULE_AUTHOR("Ricardo Martins <rasm@fe.up.pt>"); MODULE_AUTHOR("James Nuss <jamesnuss@nanometrics.ca>"); MODULE_DESCRIPTION("Use GPIO pin as PPS source"); MODULE_LICENSE("GPL"); -MODULE_VERSION("1.0.0"); +MODULE_VERSION("1.1.0"); diff --git a/include/linux/pps-gpio.h b/include/linux/pps-gpio.h index 56f35dd3d01d..f028d2cda6f5 100644 --- a/include/linux/pps-gpio.h +++ b/include/linux/pps-gpio.h @@ -23,10 +23,9 @@ #define _PPS_GPIO_H struct pps_gpio_platform_data { + struct gpio_desc *gpio_pin; bool assert_falling_edge; bool capture_clear; - unsigned int gpio_pin; - const char *gpio_label; }; #endif /* _PPS_GPIO_H */ -- 2.12.3 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v11 2/3] dt-bindings: pps: pps-gpio PPS ECHO implementation 2018-11-29 0:26 ` [PATCH v11 1/3] pps: descriptor-based gpio Tom Burkart @ 2018-11-29 0:26 ` Tom Burkart 2018-11-29 0:26 ` [PATCH v11 3/3] pps: pps-gpio pps-echo implementation Tom Burkart 0 siblings, 1 reply; 4+ messages in thread From: Tom Burkart @ 2018-11-29 0:26 UTC (permalink / raw) To: Linux kernel mailing list; +Cc: Tom Burkart, devicetree, Lukas Senger This patch implements the device tree changes required for the pps echo functionality for pps-gpio, that sysfs claims is available already. This patch was originally written by Lukas Senger as part of a masters thesis project and modified for inclusion into the linux kernel by Tom Burkart. Signed-off-by: Lukas Senger <lukas@fridolin.com> Signed-off-by: Tom Burkart <tom@aussec.com> --- Documentation/devicetree/bindings/pps/pps-gpio.txt | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Documentation/devicetree/bindings/pps/pps-gpio.txt b/Documentation/devicetree/bindings/pps/pps-gpio.txt index 3683874832ae..3760c271f211 100644 --- a/Documentation/devicetree/bindings/pps/pps-gpio.txt +++ b/Documentation/devicetree/bindings/pps/pps-gpio.txt @@ -7,9 +7,14 @@ Required properties: - compatible: should be "pps-gpio" - gpios: one PPS GPIO in the format described by ../gpio/gpio.txt +Additional required properties for the PPS ECHO functionality: +- echo-gpios: one PPS ECHO GPIO in the format described by ../gpio/gpio.txt +- echo-active-ms: duration in ms of the active portion of the echo pulse + Optional properties: - assert-falling-edge: when present, assert is indicated by a falling edge (instead of by a rising edge) +- invert-pps-echo: when present, invert the PPS ECHO pulse Example: pps { @@ -19,5 +24,9 @@ Example: gpios = <&gpio1 26 GPIO_ACTIVE_HIGH>; assert-falling-edge; + echo-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>; + echo-active-ms = <100>; + invert-pps-echo; + compatible = "pps-gpio"; }; -- 2.12.3 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v11 3/3] pps: pps-gpio pps-echo implementation 2018-11-29 0:26 ` [PATCH v11 2/3] dt-bindings: pps: pps-gpio PPS ECHO implementation Tom Burkart @ 2018-11-29 0:26 ` Tom Burkart 0 siblings, 0 replies; 4+ messages in thread From: Tom Burkart @ 2018-11-29 0:26 UTC (permalink / raw) To: Linux kernel mailing list; +Cc: Tom Burkart, Lukas Senger This patch implements the pps echo functionality for pps-gpio, that sysfs claims is available already. Configuration is done via device tree bindings. This patch was originally written by Lukas Senger as part of a masters thesis project and modified for inclusion into the linux kernel by Tom Burkart. Signed-off-by: Lukas Senger <lukas@fridolin.com> Signed-off-by: Tom Burkart <tom@aussec.com> --- drivers/pps/clients/pps-gpio.c | 102 +++++++++++++++++++++++++++++++++++++++-- include/linux/pps-gpio.h | 3 ++ 2 files changed, 102 insertions(+), 3 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index 5d764dceabc5..d74420d61b5f 100644 --- a/drivers/pps/clients/pps-gpio.c +++ b/drivers/pps/clients/pps-gpio.c @@ -35,6 +35,8 @@ #include <linux/list.h> #include <linux/of_device.h> #include <linux/of_gpio.h> +#include <linux/timer.h> +#include <linux/jiffies.h> /* Info for each registered platform device */ struct pps_gpio_device_data { @@ -42,8 +44,14 @@ struct pps_gpio_device_data { struct pps_device *pps; /* PPS source device */ struct pps_source_info info; /* PPS source information */ struct gpio_desc *gpio_pin; /* GPIO port descriptors */ + struct gpio_desc *echo_pin; + struct timer_list echo_timer; /* timer to reset echo active state */ bool assert_falling_edge; bool capture_clear; + bool enable_pps_echo; + bool invert_pps_echo; + unsigned int echo_active_ms; /* PPS echo active duration */ + unsigned long echo_timeout; /* timer timeout value in jiffies */ }; /* @@ -64,19 +72,60 @@ static irqreturn_t pps_gpio_irq_handler(int irq, void *data) rising_edge = gpiod_get_value(info->gpio_pin); if ((rising_edge && !info->assert_falling_edge) || (!rising_edge && info->assert_falling_edge)) - pps_event(info->pps, &ts, PPS_CAPTUREASSERT, NULL); + pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data); else if (info->capture_clear && ((rising_edge && info->assert_falling_edge) || (!rising_edge && !info->assert_falling_edge))) - pps_event(info->pps, &ts, PPS_CAPTURECLEAR, NULL); + pps_event(info->pps, &ts, PPS_CAPTURECLEAR, data); return IRQ_HANDLED; } +static void pps_gpio_echo(struct pps_device *pps, int event, void *data) +{ + /* add_timer() needs to write into info->echo_timer */ + struct pps_gpio_device_data *info; + + info = data; + + switch (event) { + case PPS_CAPTUREASSERT: + if (pps->params.mode & PPS_ECHOASSERT) + gpiod_set_value(info->echo_pin, + info->invert_pps_echo ? 0 : 1); + break; + + case PPS_CAPTURECLEAR: + if (pps->params.mode & PPS_ECHOCLEAR) + gpiod_set_value(info->echo_pin, + info->invert_pps_echo ? 0 : 1); + break; + } + + /* fire the timer */ + if (info->pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) { + info->echo_timer.expires = jiffies + info->echo_timeout; + add_timer(&info->echo_timer); + } +} + +/* Timer callback to reset the echo pin to the inactive state */ +static void pps_gpio_echo_timer_callback(struct timer_list *t) +{ + const struct pps_gpio_device_data *info; + + info = from_timer(info, t, echo_timer); + + gpiod_set_value(info->echo_pin, + info->invert_pps_echo ? 1 : 0); +} + static int pps_gpio_setup(struct platform_device *pdev) { struct pps_gpio_device_data *data = platform_get_drvdata(pdev); struct device_node *np = pdev->dev.of_node; + int ret; + u32 value; data->gpio_pin = devm_gpiod_get(&pdev->dev, NULL, /* request "gpios" */ @@ -87,8 +136,40 @@ static int pps_gpio_setup(struct platform_device *pdev) return PTR_ERR(data->gpio_pin); } + if (of_property_read_bool(np, "echo-gpios")) { + data->enable_pps_echo = true; + + data->echo_pin = devm_gpiod_get(&pdev->dev, + "echo", + GPIOD_OUT_LOW); + if (IS_ERR(data->echo_pin)) { + dev_err(&pdev->dev, "failed to request ECHO GPIO\n"); + return PTR_ERR(data->echo_pin); + } + + ret = of_property_read_u32(np, + "echo-active-ms", + &value); + if (ret) { + dev_err(&pdev->dev, + "failed to get echo-active-ms from OF\n"); + return ret; + } + data->echo_active_ms = value; + /* sanity check on echo_active_ms */ + if (!data->echo_active_ms || data->echo_active_ms > 999) { + dev_err(&pdev->dev, + "echo-active-ms: %u - bad value from OF\n", + data->echo_active_ms); + return -EINVAL; + } + } + if (of_property_read_bool(np, "assert-falling-edge")) data->assert_falling_edge = true; + + if (of_property_read_bool(np, "invert-pps-echo")) + data->invert_pps_echo = true; return 0; } @@ -122,9 +203,14 @@ static int pps_gpio_probe(struct platform_device *pdev) /* GPIO setup */ if (pdata) { data->gpio_pin = pdata->gpio_pin; + data->echo_pin = pdata->echo_pin; + if (pdata->echo_pin != NULL) + data->enable_pps_echo = true; data->assert_falling_edge = pdata->assert_falling_edge; data->capture_clear = pdata->capture_clear; + data->invert_pps_echo = pdata->invert_pps_echo; + data->echo_active_ms = pdata->echo_active_ms; } else { ret = pps_gpio_setup(pdev); if (ret) @@ -148,6 +234,11 @@ static int pps_gpio_probe(struct platform_device *pdev) data->info.owner = THIS_MODULE; snprintf(data->info.name, PPS_MAX_NAME_LEN - 1, "%s.%d", pdev->name, pdev->id); + if (data->enable_pps_echo) { + data->info.echo = pps_gpio_echo; + data->echo_timeout = msecs_to_jiffies(data->echo_active_ms); + timer_setup(&data->echo_timer, pps_gpio_echo_timer_callback, 0); + } /* register PPS source */ pps_default_params = PPS_CAPTUREASSERT | PPS_OFFSETASSERT; @@ -180,6 +271,11 @@ static int pps_gpio_remove(struct platform_device *pdev) struct pps_gpio_device_data *data = platform_get_drvdata(pdev); pps_unregister_source(data->pps); + if (data->enable_pps_echo) { + del_timer_sync(&data->echo_timer); + /* reset echo pin in any case */ + gpiod_set_value(data->echo_pin, data->invert_pps_echo ? 1 : 0); + } dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq); return 0; } @@ -204,4 +300,4 @@ MODULE_AUTHOR("Ricardo Martins <rasm@fe.up.pt>"); MODULE_AUTHOR("James Nuss <jamesnuss@nanometrics.ca>"); MODULE_DESCRIPTION("Use GPIO pin as PPS source"); MODULE_LICENSE("GPL"); -MODULE_VERSION("1.1.0"); +MODULE_VERSION("1.2.0"); diff --git a/include/linux/pps-gpio.h b/include/linux/pps-gpio.h index f028d2cda6f5..5390f18c73a5 100644 --- a/include/linux/pps-gpio.h +++ b/include/linux/pps-gpio.h @@ -24,8 +24,11 @@ struct pps_gpio_platform_data { struct gpio_desc *gpio_pin; + struct gpio_desc *echo_pin; bool assert_falling_edge; bool capture_clear; + bool invert_pps_echo; + unsigned int echo_active_ms; }; #endif /* _PPS_GPIO_H */ -- 2.12.3 ^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-11-29 0:27 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2018-11-29 0:26 [PATCH v11 0/3] PPS: pps-gpio PPS ECHO implementation Tom Burkart 2018-11-29 0:26 ` [PATCH v11 1/3] pps: descriptor-based gpio Tom Burkart 2018-11-29 0:26 ` [PATCH v11 2/3] dt-bindings: pps: pps-gpio PPS ECHO implementation Tom Burkart 2018-11-29 0:26 ` [PATCH v11 3/3] pps: pps-gpio pps-echo implementation Tom Burkart
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