Re: [RFC v2 2/3] pinctrl: Implementation of the generic scmi-pinctrl driver
From: Oleksii Moisieiev
Date: Thu May 11 2023 - 06:23:29 EST
Hi Cristian,
Please see below.
On 05.05.23 23:01, Cristian Marussi wrote:
> On Wed, Apr 26, 2023 at 01:26:37PM +0000, Oleksii Moisieiev wrote:
>> scmi-pinctrl driver implements pinctrl driver interface and using
>> SCMI protocol to redirect messages from pinctrl subsystem SDK to
>> SCP firmware, which does the changes in HW.
>>
>> This setup expects SCP firmware (or similar system, such as ATF)
>> to be installed on the platform, which implements pinctrl driver
>> for the specific platform.
>>
>> SCMI-Pinctrl driver should be configured from the device-tree and uses
>> generic device-tree mappings for the configuration.
>>
>
> Hi Oleksii,
>
> just a few remarks down below.
>
>> Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
>> ---
>> MAINTAINERS | 1 +
>> drivers/pinctrl/Kconfig | 9 +
>> drivers/pinctrl/Makefile | 1 +
>> drivers/pinctrl/pinctrl-scmi.c | 578 +++++++++++++++++++++++++++++++++
>> 4 files changed, 589 insertions(+)
>> create mode 100644 drivers/pinctrl/pinctrl-scmi.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 0d251ebac437..ba9e3aea6176 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -20322,6 +20322,7 @@ M: Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
>> L: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>> S: Maintained
>> F: drivers/firmware/arm_scmi/pinctrl.c
>> +F: drivers/pinctrl/pinctrl-scmi.c
>>
>> SYSTEM RESET/SHUTDOWN DRIVERS
>> M: Sebastian Reichel <sre@xxxxxxxxxx>
>> diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
>> index dcb53c4a9584..16bf2c67f095 100644
>> --- a/drivers/pinctrl/Kconfig
>> +++ b/drivers/pinctrl/Kconfig
>> @@ -552,4 +552,13 @@ source "drivers/pinctrl/uniphier/Kconfig"
>> source "drivers/pinctrl/visconti/Kconfig"
>> source "drivers/pinctrl/vt8500/Kconfig"
>>
>> +config PINCTRL_SCMI
>> + bool "Pinctrl driver controlled via SCMI interface"
>
> Why not a tristate ? The core SCMI stack can be compiled as module with
> all the protocols...at least for testing is useful to have this driver
> as M.
>
Yes, thanks. Will fix in v3.
>> + depends on ARM_SCMI_PROTOCOL || COMPILE_TEST
>> + help
>> + This driver provides support for pinctrl which is controlled
>> + by firmware that implements the SCMI interface.
>> + It uses SCMI Message Protocol to interact with the
>> + firmware providing all the pinctrl controls.
>> +
>> endif
>> diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
>> index d5939840bb2a..21366db4f4f4 100644
>> --- a/drivers/pinctrl/Makefile
>> +++ b/drivers/pinctrl/Makefile
>> @@ -51,6 +51,7 @@ obj-$(CONFIG_PINCTRL_TB10X) += pinctrl-tb10x.o
>> obj-$(CONFIG_PINCTRL_THUNDERBAY) += pinctrl-thunderbay.o
>> obj-$(CONFIG_PINCTRL_ZYNQMP) += pinctrl-zynqmp.o
>> obj-$(CONFIG_PINCTRL_ZYNQ) += pinctrl-zynq.o
>> +obj-$(CONFIG_PINCTRL_SCMI) += pinctrl-scmi.o
>>
>> obj-y += actions/
>> obj-$(CONFIG_ARCH_ASPEED) += aspeed/
>> diff --git a/drivers/pinctrl/pinctrl-scmi.c b/drivers/pinctrl/pinctrl-scmi.c
>> new file mode 100644
>> index 000000000000..8401db1d030b
>> --- /dev/null
>> +++ b/drivers/pinctrl/pinctrl-scmi.c
>> @@ -0,0 +1,578 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * System Control and Power Interface (SCMI) Protocol based pinctrl driver
>> + *
>> + * Copyright (C) 2023 EPAM
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/err.h>
>> +#include <linux/of.h>
>> +#include <linux/module.h>
>> +#include <linux/seq_file.h>
>> +
>> +#include <linux/pinctrl/machine.h>
>> +#include <linux/pinctrl/pinconf.h>
>> +#include <linux/pinctrl/pinconf-generic.h>
>> +#include <linux/pinctrl/pinctrl.h>
>> +#include <linux/pinctrl/pinmux.h>
>> +#include <linux/scmi_protocol.h>
>> +#include <linux/slab.h>
>> +
>> +#include "pinctrl-utils.h"
>> +#include "core.h"
>> +#include "pinconf.h"
>> +
>> +#define DRV_NAME "scmi-pinctrl"
>> +
>> +static const struct scmi_pinctrl_proto_ops *pinctrl_ops;
>> +
>> +struct scmi_pinctrl_funcs {
>> + unsigned int num_groups;
>> + const char **groups;
>> +};
>> +
>> +struct scmi_pinctrl {
>> + struct device *dev;
>> + struct scmi_protocol_handle *ph;
>> + struct pinctrl_dev *pctldev;
>> + struct pinctrl_desc pctl_desc;
>> + struct scmi_pinctrl_funcs *functions;
>> + unsigned int nr_functions;
>> + char **groups;
>> + unsigned int nr_groups;
>> + struct pinctrl_pin_desc *pins;
>> + unsigned int nr_pins;
>> +};
>> +
>> +static int pinctrl_scmi_get_groups_count(struct pinctrl_dev *pctldev)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->get_count(pmx->ph, GROUP_TYPE);
>> +}
>> +
>> +static const char *pinctrl_scmi_get_group_name(struct pinctrl_dev *pctldev,
>> + unsigned int selector)
>> +{
>> + int ret;
>> + const char *name;
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return NULL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return NULL;
>> +
>> + ret = pinctrl_ops->get_name(pmx->ph, selector, GROUP_TYPE, &name);
>> + if (ret) {
>> + dev_err(pmx->dev, "get name failed with err %d", ret);
>> + return NULL;
>> + }
>> +
>> + return name;
>> +}
>> +
>> +static int pinctrl_scmi_get_group_pins(struct pinctrl_dev *pctldev,
>> + unsigned int selector,
>> + const unsigned int **pins,
>> + unsigned int *num_pins)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->get_group_pins(pmx->ph, selector,
>> + pins, num_pins);
>> +}
>> +
>> +static void pinctrl_scmi_pin_dbg_show(struct pinctrl_dev *pctldev,
>> + struct seq_file *s,
>> + unsigned int offset)
>> +{
>> + seq_puts(s, DRV_NAME);
>> +}
>> +
>> +#ifdef CONFIG_OF
>> +static int pinctrl_scmi_dt_node_to_map(struct pinctrl_dev *pctldev,
>> + struct device_node *np_config,
>> + struct pinctrl_map **map,
>> + u32 *num_maps)
>> +{
>> + return pinconf_generic_dt_node_to_map(pctldev, np_config, map,
>> + num_maps, PIN_MAP_TYPE_INVALID);
>> +}
>> +
>> +static void pinctrl_scmi_dt_free_map(struct pinctrl_dev *pctldev,
>> + struct pinctrl_map *map, u32 num_maps)
>> +{
>> + kfree(map);
>> +}
>> +
>> +#endif /* CONFIG_OF */
>> +
>> +static const struct pinctrl_ops pinctrl_scmi_pinctrl_ops = {
>> + .get_groups_count = pinctrl_scmi_get_groups_count,
>> + .get_group_name = pinctrl_scmi_get_group_name,
>> + .get_group_pins = pinctrl_scmi_get_group_pins,
>> + .pin_dbg_show = pinctrl_scmi_pin_dbg_show,
>> +#ifdef CONFIG_OF
>> + .dt_node_to_map = pinctrl_scmi_dt_node_to_map,
>> + .dt_free_map = pinctrl_scmi_dt_free_map,
>> +#endif
>> +};
>> +
>> +static int pinctrl_scmi_get_functions_count(struct pinctrl_dev *pctldev)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->get_count(pmx->ph, FUNCTION_TYPE);
>> +}
>> +
>> +static const char *pinctrl_scmi_get_function_name(struct pinctrl_dev *pctldev,
>> + unsigned int selector)
>> +{
>> + int ret;
>> + const char *name;
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return NULL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return NULL;
>> +
>> + ret = pinctrl_ops->get_name(pmx->ph, selector, FUNCTION_TYPE, &name);
>> + if (ret) {
>> + dev_err(pmx->dev, "get name failed with err %d", ret);
>> + return NULL;
>> + }
>> +
>> + return name;
>> +}
>> +
>> +static int pinctrl_scmi_get_function_groups(struct pinctrl_dev *pctldev,
>> + unsigned int selector,
>> + const char * const **groups,
>> + unsigned int * const num_groups)
>> +{
>> + const unsigned int *group_ids;
>> + int ret, i;
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph || !groups || !num_groups)
>> + return -EINVAL;
>> +
>> + if (selector < pmx->nr_functions &&
>> + pmx->functions[selector].num_groups) {
>> + *groups = (const char * const *)pmx->functions[selector].groups;
>> + *num_groups = pmx->functions[selector].num_groups;
>> + return 0;
>> + }
>> +
>> + ret = pinctrl_ops->get_function_groups(pmx->ph, selector,
>> + &pmx->functions[selector].num_groups,
>> + &group_ids);
>> + if (ret) {
>> + dev_err(pmx->dev, "Unable to get function groups, err %d", ret);
>> + return ret;
>> + }
>> +
>> + *num_groups = pmx->functions[selector].num_groups;
>> + if (!*num_groups)
>> + return -EINVAL;
>> +
>> + pmx->functions[selector].groups =
>> + devm_kcalloc(pmx->dev, *num_groups,
>> + sizeof(*pmx->functions[selector].groups),
>> + GFP_KERNEL);
>> + if (!pmx->functions[selector].groups)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < *num_groups; i++) {
>> + pmx->functions[selector].groups[i] =
>> + pinctrl_scmi_get_group_name(pmx->pctldev,
>> + group_ids[i]);
>> + if (!pmx->functions[selector].groups[i]) {
>> + ret = -ENOMEM;
>> + goto error;
>> + }
>> + }
>> +
>> + *groups = (const char * const *)pmx->functions[selector].groups;
>> +
>> + return 0;
>> +
>> +error:
>> + kfree(pmx->functions[selector].groups);
>
> devm_kfree ?
>
Thanks, fixed.
>> +
>> + return ret;
>> +}
>> +
>> +static int pinctrl_scmi_func_set_mux(struct pinctrl_dev *pctldev,
>> + unsigned int selector, unsigned int group)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->set_mux(pmx->ph, selector, group);
>> +}
>> +
>> +static int pinctrl_scmi_request(struct pinctrl_dev *pctldev,
>> + unsigned int offset)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->request_pin(pmx->ph, offset);
>> +}
>> +
>> +static int pinctrl_scmi_free(struct pinctrl_dev *pctldev, unsigned int offset)
>> +{
>> + struct scmi_pinctrl *pmx;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + return pinctrl_ops->free_pin(pmx->ph, offset);
>> +}
>> +
>> +static const struct pinmux_ops pinctrl_scmi_pinmux_ops = {
>> + .request = pinctrl_scmi_request,
>> + .free = pinctrl_scmi_free,
>> + .get_functions_count = pinctrl_scmi_get_functions_count,
>> + .get_function_name = pinctrl_scmi_get_function_name,
>> + .get_function_groups = pinctrl_scmi_get_function_groups,
>> + .set_mux = pinctrl_scmi_func_set_mux,
>> +};
>> +
>> +static int pinctrl_scmi_pinconf_get(struct pinctrl_dev *pctldev,
>> + unsigned int _pin,
>> + unsigned long *config)
>> +{
>> + int ret;
>> + struct scmi_pinctrl *pmx;
>> + enum pin_config_param config_type;
>> + unsigned long config_value;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph || !config)
>> + return -EINVAL;
>> +
>> + config_type = pinconf_to_config_param(*config);
>> +
>> + ret = pinctrl_ops->get_config(pmx->ph, _pin, PIN_TYPE, config_type,
>> + (u32 *)&config_value);
>> + if (ret)
>> + return ret;
>> +
>> + *config = pinconf_to_config_packed(config_type, config_value);
>> +
>> + return 0;
>> +}
>> +
>> +static int pinctrl_scmi_pinconf_set(struct pinctrl_dev *pctldev,
>> + unsigned int _pin,
>> + unsigned long *configs,
>> + unsigned int num_configs)
>> +{
>> + int i, ret;
>> + struct scmi_pinctrl *pmx;
>> + enum pin_config_param config_type;
>> + unsigned long config_value;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph || !configs || num_configs == 0)
>> + return -EINVAL;
>> +
>> + for (i = 0; i < num_configs; i++) {
>> + config_type = pinconf_to_config_param(configs[i]);
>> + config_value = pinconf_to_config_argument(configs[i]);
>> +
>> + ret = pinctrl_ops->set_config(pmx->ph, _pin, PIN_TYPE, config_type,
>> + config_value);
>> + if (ret) {
>> + dev_err(pmx->dev, "Error parsing config %ld\n",
>> + configs[i]);
>> + break;
>> + }
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int pinctrl_scmi_pinconf_group_set(struct pinctrl_dev *pctldev,
>> + unsigned int group,
>> + unsigned long *configs,
>> + unsigned int num_configs)
>> +{
>> + int i, ret;
>> + struct scmi_pinctrl *pmx;
>> + enum pin_config_param config_type;
>> + unsigned long config_value;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph || !configs || num_configs == 0)
>> + return -EINVAL;
>> +
>> + for (i = 0; i < num_configs; i++) {
>> + config_type = pinconf_to_config_param(configs[i]);
>> + config_value = pinconf_to_config_argument(configs[i]);
>> +
>> + ret = pinctrl_ops->set_config(pmx->ph, group, GROUP_TYPE,
>> + config_type, config_value);
>> + if (ret) {
>> + dev_err(pmx->dev, "Error parsing config = %ld",
>> + configs[i]);
>> + break;
>> + }
>> + }
>> +
>> + return ret;
>> +};
>> +
>> +static int pinctrl_scmi_pinconf_group_get(struct pinctrl_dev *pctldev,
>> + unsigned int _pin,
>> + unsigned long *config)
>> +{
>> + int ret;
>> + struct scmi_pinctrl *pmx;
>> + enum pin_config_param config_type;
>> + unsigned long config_value;
>> +
>> + if (!pctldev)
>> + return -EINVAL;
>> +
>> + pmx = pinctrl_dev_get_drvdata(pctldev);
>> +
>> + if (!pmx || !pmx->ph || !config)
>> + return -EINVAL;
>> +
>> + config_type = pinconf_to_config_param(*config);
>> +
>> + ret = pinctrl_ops->get_config(pmx->ph, _pin, GROUP_TYPE,
>> + config_type, (u32 *)&config_value);
>> + if (ret)
>> + return ret;
>> +
>> + *config = pinconf_to_config_packed(config_type, config_value);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct pinconf_ops pinctrl_scmi_pinconf_ops = {
>> + .is_generic = true,
>> + .pin_config_get = pinctrl_scmi_pinconf_get,
>> + .pin_config_set = pinctrl_scmi_pinconf_set,
>> + .pin_config_group_set = pinctrl_scmi_pinconf_group_set,
>> + .pin_config_group_get = pinctrl_scmi_pinconf_group_get,
>> + .pin_config_config_dbg_show = pinconf_generic_dump_config,
>> +};
>> +
>> +static int pinctrl_scmi_get_pins(struct scmi_pinctrl *pmx,
>> + unsigned int *nr_pins,
>> + const struct pinctrl_pin_desc **pins)
>> +{
>> + int ret, i;
>> +
>> + if (!pmx || !pmx->ph)
>> + return -EINVAL;
>> +
>> + if (!pins || !nr_pins)
>> + return -EINVAL;
>> +
>> + if (pmx->nr_pins) {
>> + *pins = pmx->pins;
>> + *nr_pins = pmx->nr_pins;
>> + return 0;
>> + }
>> +
>> + *nr_pins = pinctrl_ops->get_count(pmx->ph, PIN_TYPE);
>> +
>> + pmx->nr_pins = *nr_pins;
>> + pmx->pins = devm_kmalloc_array(pmx->dev, *nr_pins, sizeof(*pmx->pins),
>> + GFP_KERNEL);
>> + if (!pmx->pins)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < *nr_pins; i++) {
>> + pmx->pins[i].number = i;
>> + ret = pinctrl_ops->get_name(pmx->ph, i, PIN_TYPE,
>> + &pmx->pins[i].name);
>> + if (ret) {
>> + dev_err(pmx->dev, "Can't get name for pin %d: rc %d",
>> + i, ret);
>> + goto err;
>> + }
>> + }
>> +
>> + *pins = pmx->pins;
>> + dev_dbg(pmx->dev, "got pins %d", *nr_pins);
>> +
>> + return 0;
>> + err:
>> + kfree(pmx->pins);
> devm_kfree ? but anyway when this fails it will trigger the _probe to
> fail so all devres will be released..so not needed probably at the end.
>
>> + pmx->nr_pins = 0;
>> +
>> + return ret;
>> +}
>> +
>> +static const struct scmi_device_id scmi_id_table[] = {
>> + { SCMI_PROTOCOL_PINCTRL, "pinctrl" },
>> + { },
>> +};
>> +MODULE_DEVICE_TABLE(scmi, scmi_id_table);
>> +
>> +static int scmi_pinctrl_probe(struct scmi_device *sdev)
>> +{
>> + int ret;
>> + struct scmi_pinctrl *pmx;
>> + const struct scmi_handle *handle;
>> + struct scmi_protocol_handle *ph;
>> +
>> + if (!sdev || !sdev->handle)
>> + return -EINVAL;
>> +
>> + handle = sdev->handle;
>> +
>> + pinctrl_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PINCTRL,
>> + &ph);
>> + if (IS_ERR(pinctrl_ops))
>> + return PTR_ERR(pinctrl_ops);
>> +
>> + pmx = devm_kzalloc(&sdev->dev, sizeof(*pmx), GFP_KERNEL);
>> + if (!pmx)
>> + return -ENOMEM;
>> +
>> + pmx->ph = ph;
>> +
>> + pmx->dev = &sdev->dev;
>> + pmx->pctl_desc.name = DRV_NAME;
>> + pmx->pctl_desc.owner = THIS_MODULE;
>> + pmx->pctl_desc.pctlops = &pinctrl_scmi_pinctrl_ops;
>> + pmx->pctl_desc.pmxops = &pinctrl_scmi_pinmux_ops;
>> + pmx->pctl_desc.confops = &pinctrl_scmi_pinconf_ops;
>> +
>> + ret = pinctrl_scmi_get_pins(pmx, &pmx->pctl_desc.npins,
>> + &pmx->pctl_desc.pins);
>> + if (ret)
>> + goto clean;
>> +
>> + ret = devm_pinctrl_register_and_init(&sdev->dev, &pmx->pctl_desc, pmx,
>> + &pmx->pctldev);
>> + if (ret) {
>> + dev_err(&sdev->dev, "could not register: %i\n", ret);
>> + goto clean;
>> + }
>> +
>> + pmx->nr_functions = pinctrl_scmi_get_functions_count(pmx->pctldev);
>> + pmx->nr_groups = pinctrl_scmi_get_groups_count(pmx->pctldev);
>> +
>> + if (pmx->nr_functions) {
>> + pmx->functions =
>> + devm_kcalloc(&sdev->dev, pmx->nr_functions,
>> + sizeof(*pmx->functions),
>> + GFP_KERNEL);
>> + if (!pmx->functions) {
>> + ret = -ENOMEM;
>> + goto clean;
>> + }
>> + }
>> +
>> + if (pmx->nr_groups) {
>> + pmx->groups =
>> + devm_kcalloc(&sdev->dev, pmx->nr_groups,
>> + sizeof(*pmx->groups),
>> + GFP_KERNEL);
>> + if (!pmx->groups) {
>> + ret = -ENOMEM;
>> + goto clean;
>> + }
>> + }
>> +
>> + return pinctrl_enable(pmx->pctldev);
>> +
>> +clean:
>> + if (pmx) {
>> + kfree(pmx->functions);
>> + kfree(pmx->groups);
>> + }
>> +
>> + kfree(pmx);
>
> All of these are devres allocated...it does not seem to me that they
> require explicit freeing on the _probe() failure path.
> (indeed you dont need even a .remove function)
>
Removed this block.
> Thanks,
> Cristian