Re: [PATCH v6 3/3] pinctrl: Add Xilinx ZynqMP pinctrl driver support
From: Andy Shevchenko
Date: Fri Apr 23 2021 - 11:54:18 EST
On Thu, Apr 22, 2021 at 11:31 AM Sai Krishna Potthuri
<lakshmi.sai.krishna.potthuri@xxxxxxxxxx> wrote:
>
> Adding pinctrl driver for Xilinx ZynqMP platform.
> This driver queries pin information from firmware and registers
> pin control accordingly.
>
> Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xxxxxxxxxx>
You may reduce the number of LOCs by joining some lines. See below.
...
> +config PINCTRL_ZYNQMP
> + tristate "Pinctrl driver for Xilinx ZynqMP"
> + depends on ZYNQMP_FIRMWARE
> + select PINMUX
> + select GENERIC_PINCONF
> + default ZYNQMP_FIRMWARE
> + help
> + This selects the pinctrl driver for Xilinx ZynqMP platform.
> + This driver will query the pin information from the firmware
> + and allow configuring the pins.
> + Configuration can include the mux function to select on those
> + pin(s)/group(s), and various pin configuration parameters
> + such as pull-up, slew rate, etc.
Missed module name.
...
> +/*
> + * ZynqMP pin controller
> + *
> + * Copyright (C) 2020 Xilinx, Inc.
2021?
> + *
> + * Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xxxxxxxxxx>
> + * Rajan Vaja <rajan.vaja@xxxxxxxxxx>
> + */
...
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/firmware/xlnx-zynqmp.h>
...
> +static int zynqmp_pinconf_cfg_get(struct pinctrl_dev *pctldev,
> + unsigned int pin,
> + unsigned long *config)
> +{
> + unsigned int arg, param = pinconf_to_config_param(*config);
> + int ret;
> + if (pin >= zynqmp_desc.npins)
> + return -EOPNOTSUPP;
Is it possible?
> + switch (param) {
> + case PIN_CONFIG_SLEW_RATE:
> + param = PM_PINCTRL_CONFIG_SLEW_RATE;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + break;
> + case PIN_CONFIG_BIAS_PULL_UP:
> + param = PM_PINCTRL_CONFIG_PULL_CTRL;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + if (arg != PM_PINCTRL_BIAS_PULL_UP)
> + return -EINVAL;
Error code being shadowed. Instead check it here properly.
> + arg = 1;
> + break;
> + case PIN_CONFIG_BIAS_PULL_DOWN:
> + param = PM_PINCTRL_CONFIG_PULL_CTRL;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + if (arg != PM_PINCTRL_BIAS_PULL_DOWN)
> + return -EINVAL;
Ditto.
> + arg = 1;
> + break;
> + case PIN_CONFIG_BIAS_DISABLE:
> + param = PM_PINCTRL_CONFIG_BIAS_STATUS;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + if (arg != PM_PINCTRL_BIAS_DISABLE)
> + return -EINVAL;
Ditto.
> + arg = 1;
> + break;
> + case PIN_CONFIG_POWER_SOURCE:
> + param = PM_PINCTRL_CONFIG_VOLTAGE_STATUS;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + break;
> + case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
> + param = PM_PINCTRL_CONFIG_SCHMITT_CMOS;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + break;
> + case PIN_CONFIG_DRIVE_STRENGTH:
> + param = PM_PINCTRL_CONFIG_DRIVE_STRENGTH;
> + ret = zynqmp_pm_pinctrl_get_config(pin, param, &arg);
> + switch (arg) {
> + case PM_PINCTRL_DRIVE_STRENGTH_2MA:
> + arg = DRIVE_STRENGTH_2MA;
> + break;
> + case PM_PINCTRL_DRIVE_STRENGTH_4MA:
> + arg = DRIVE_STRENGTH_4MA;
> + break;
> + case PM_PINCTRL_DRIVE_STRENGTH_8MA:
> + arg = DRIVE_STRENGTH_8MA;
> + break;
> + case PM_PINCTRL_DRIVE_STRENGTH_12MA:
> + arg = DRIVE_STRENGTH_12MA;
> + break;
> + default:
> + /* Invalid drive strength */
> + dev_warn(pctldev->dev,
> + "Invalid drive strength for pin %d\n",
> + pin);
> + return -EINVAL;
> + }
> + break;
> + default:
> + ret = -EOPNOTSUPP;
> + break;
> + }
> +
> + if (ret)
> + return ret;
> +
> + param = pinconf_to_config_param(*config);
> + *config = pinconf_to_config_packed(param, arg);
> +
> + return 0;
> +}
...
> + ret = -EOPNOTSUPP;
Isn't it ENOTSUP for all cases here?
...
> + ret = zynqmp_pm_query_data(qdata, payload);
> + if (ret)
> + return ret;
> +
> + *ngroups = payload[1];
> +
> + return ret;
return 0;
...
> + * Query firmware to get group IDs for each function. Firmware returns
> + * group IDs. Based on group index for the function, group names in
on the group
> + * the function are stored. For example, the first group in "eth0" function
> + * is named as "eth0_0" and second group as "eth0_1" and so on.
and the second
> + *
> + * Based on the group ID received from the firmware, function stores name of
> + * the group for that group ID. For example, if "eth0" first group ID
> + * is x, groups[x] name will be stored as "eth0_0".
> + *
> + * Once done for each function, each function would have its group names
> + * and each groups would also have their names.
each group
...
> +done:
> + func->groups = fgroups;
> +
> + return ret;
return 0; ?
...
> + *nfuncs = payload[1];
> +
> + return ret;
Ditto.
...
> + ret = zynqmp_pm_query_data(qdata, payload);
> + if (ret)
> + return ret;
> +
> + memcpy(groups, &payload[1], PINCTRL_GET_PIN_GROUPS_RESP_LEN);
> +
> + return ret;
Ditto.
...
> + * Query firmware to get groups available for the given pin.
> + * Based on the firmware response(group IDs for the pin), add
> + * pin number to the respective group's pin array.
> + *
> + * Once all pins are queries, each groups would have its number
each group
> + * of pins and pin numbers data.
...
> + return ret;
return 0;
...
> + * Query number of functions and number of function groups (number
> + * of groups in given function) to allocate required memory buffers
in the given
> + * for functions and groups. Once buffers are allocated to store
> + * functions and groups data, query and store required information
> + * (number of groups and group names for each function, number of
> + * pins and pin numbers for each group).
...
> + pctrl->funcs = funcs;
> + pctrl->groups = groups;
> +
> + return ret;
return 0;
...
> + *npins = payload[1];
> +
> + return ret;
Ditto.
...
> + dev_err(&pdev->dev, "pin desc prepare fail with %d\n",
> + ret);
One line.
...
> + dev_err(&pdev->dev, "function info prepare fail with %d\n",
> + ret);
Ditto.
...
> + pctrl->pctrl = pinctrl_register(&zynqmp_desc, &pdev->dev, pctrl);
devm_pinctrl_register()
> + if (IS_ERR(pctrl->pctrl))
> + return PTR_ERR(pctrl->pctrl);
...
> +};
> +
Extra blank line.
> +MODULE_DEVICE_TABLE(of, zynqmp_pinctrl_of_match);
...
> +};
> +
Ditto.
> +module_platform_driver(zynqmp_pinctrl_driver);
--
With Best Regards,
Andy Shevchenko