Re: [PATCH v3 09/11] pinctrl: qcom-wcd934x: Add support to wcd934x pinctrl driver.
From: Srinivas Kandagatla
Date: Thu Oct 31 2019 - 06:31:28 EST
Thanks Stephen for reviewing this patch.
On 30/10/2019 14:50, Stephen Boyd wrote:
Quoting Srinivas Kandagatla (2019-10-29 04:26:58)
From: Yeleswarapu Nagaradhesh <nagaradh@xxxxxxxxxxxxxx>
This patch adds support to wcd934x pinctrl block found in
WCD9340/WC9341 Audio codecs.
[Srini: multiple cleanups to the code]
This goes after the author signoff and before yours. Can you add more
details too?
I agree, will fix this in next spin.
Signed-off-by: Yeleswarapu Nagaradhesh <nagaradh@xxxxxxxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/pinctrl/qcom/Kconfig | 7 +
drivers/pinctrl/qcom/Makefile | 1 +
drivers/pinctrl/qcom/pinctrl-wcd934x-gpio.c | 365 ++++++++++++++++++++
3 files changed, 373 insertions(+)
create mode 100644 drivers/pinctrl/qcom/pinctrl-wcd934x-gpio.c
diff --git a/drivers/pinctrl/qcom/pinctrl-wcd934x-gpio.c b/drivers/pinctrl/qcom/pinctrl-wcd934x-gpio.c
new file mode 100644
index 000000000000..1aff88d0bcb3
--- /dev/null
+++ b/drivers/pinctrl/qcom/pinctrl-wcd934x-gpio.c
@@ -0,0 +1,365 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2016-2017, The Linux Foundation. All rights reserved.
+// Copyright (c) 2019, Linaro Limited
+
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+
+#include "../core.h"
+#include "../pinctrl-utils.h"
+
+#define WCD_REG_DIR_CTL_OFFSET 0x42
+#define WCD_REG_VAL_CTL_OFFSET 0x43
+#define WCD_GPIO_PULL_UP 1
+#define WCD_GPIO_PULL_DOWN 2
+#define WCD_GPIO_BIAS_DISABLE 3
+#define WCD_GPIO_STRING_LEN 20
+#define WCD934X_NPINS 5
+
+/**
+ * struct wcd_gpio_pad - keep current GPIO settings
+ * @offset: offset of gpio.
+ * @is_valid: Set to false, when GPIO in high Z state.
+ * @value: value of a pin
+ * @output_enabled: Set to true if GPIO is output and false if it is input
+ * @pullup: Constant current which flow through GPIO output buffer.
+ * @strength: Drive strength of a pin
+ */
+struct wcd_gpio_pad {
+ u16 offset;
+ bool is_valid;
+ bool value;
+ bool output_enabled;
+ unsigned int pullup;
+ unsigned int strength;
+};
+
+struct wcd_gpio_priv {
+ struct device *dev;
+ struct regmap *map;
+ struct pinctrl_dev *ctrl;
+ struct gpio_chip chip;
+};
+
+static int wcd_gpio_read(struct wcd_gpio_priv *priv_data,
+ struct wcd_gpio_pad *pad, unsigned int addr)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(priv_data->map, addr, &val);
+ if (ret < 0)
+ dev_err(priv_data->dev, "%s: read 0x%x failed\n",
+ __func__, addr);
+ else
+ ret = (val >> pad->offset);
+
+ return ret;
+}
+
+static int wcd_gpio_write(struct wcd_gpio_priv *priv_data,
+ struct wcd_gpio_pad *pad, unsigned int addr,
+ unsigned int val)
+{
+ int ret;
+
+ ret = regmap_update_bits(priv_data->map, addr, (1 << pad->offset),
+ val << pad->offset);
+ if (ret < 0)
+ dev_err(priv_data->dev, "write 0x%x failed\n", addr);
Is there value in these error messages? Also, use %#x to get '0x'.
I can add ret in the err message.
I did not knew about "%#x".. nice, I will use this in future!
+
+ return ret;
+}
[...]
+
+static int wcd_pinctrl_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pinctrl_pin_desc *pindesc;
+ struct pinctrl_desc *pctrldesc;
+ struct wcd_gpio_pad *pad, *pads;
+ struct wcd_gpio_priv *priv_data;
+ u32 npins = WCD934X_NPINS;
+ char **name;
+ int i;
+
+ priv_data = devm_kzalloc(dev, sizeof(*priv_data), GFP_KERNEL);
+ if (!priv_data)
+ return -ENOMEM;
+
+ priv_data->dev = dev;
+ priv_data->map = dev_get_regmap(dev->parent, NULL);
+ if (!priv_data->map) {
+ dev_err(dev, "%s: failed to get regmap\n", __func__);
+ return -EINVAL;
+ }
+
+ pindesc = devm_kcalloc(dev, npins, sizeof(*pindesc), GFP_KERNEL);
+ if (!pindesc)
+ return -ENOMEM;
+
+ pads = devm_kcalloc(dev, npins, sizeof(*pads), GFP_KERNEL);
+ if (!pads)
+ return -ENOMEM;
Is it possible to put the pad struct around the pindesc struct? It's
sort of sad that we have to allocate a chunk of memory twice for the
pindesc and the pads when we could either use container_of() on the
pindesc or just point the pindesc driver data member to the container
structure for the qcom specific bits.
I will give that a go in next version!
+
+ pctrldesc = devm_kzalloc(dev, sizeof(*pctrldesc), GFP_KERNEL);
+ if (!pctrldesc)
+ return -ENOMEM;
+
+ pctrldesc->pctlops = &wcd_pinctrl_ops;
+ pctrldesc->confops = &wcd_pinconf_ops;
+ pctrldesc->owner = THIS_MODULE;
+ pctrldesc->name = dev_name(dev);
+ pctrldesc->pins = pindesc;
+ pctrldesc->npins = npins;
+
+ name = devm_kcalloc(dev, npins, sizeof(char *), GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ for (i = 0; i < npins; i++, pindesc++) {
+ name[i] = devm_kzalloc(dev, sizeof(char) * WCD_GPIO_STRING_LEN,
+ GFP_KERNEL);
+ if (!name[i])
+ return -ENOMEM;
+
+ pad = &pads[i];
+ pindesc->drv_data = pad;
+ pindesc->number = i;
+ snprintf(name[i], (WCD_GPIO_STRING_LEN - 1), "gpio%d", (i+1));
+ pindesc->name = name[i];
Why not use devm_kasprintf()? The 'name' array is also unnecessary?
Am not sure why its not used her, but I can do that change in next version.
+ pad->offset = i;
+ pad->is_valid = true;
+ }
+
+ priv_data->chip = wcd_gpio_chip;
+ priv_data->chip.parent = dev;
+ priv_data->chip.base = -1;
+ priv_data->chip.ngpio = npins;
+ priv_data->chip.label = dev_name(dev);
+ priv_data->chip.of_gpio_n_cells = 2;
+ priv_data->chip.can_sleep = false;
+ platform_set_drvdata(pdev, priv_data);
+
+ priv_data->ctrl = devm_pinctrl_register(dev, pctrldesc, priv_data);
+ if (IS_ERR(priv_data->ctrl)) {
+ dev_err(dev, "%s: failed to register to pinctrl\n", __func__);
+ return PTR_ERR(priv_data->ctrl);
+ }
+
+ return gpiochip_add_data(&priv_data->chip, priv_data);
WHy not use devm_gpiochip_add_data()?
Good idea, will do that in next spin.
+}
+
+static int wcd_pinctrl_remove(struct platform_device *pdev)
+{
+ struct wcd_gpio_priv *priv_data = platform_get_drvdata(pdev);
+
+ gpiochip_remove(&priv_data->chip);
+
+ return 0;
And drop this function?
+}
+
+static const struct of_device_id wcd_pinctrl_of_match[] = {
+ { .compatible = "qcom,wcd9340-pinctrl" },
+ { .compatible = "qcom,wcd9341-pinctrl" },
+ { },
Nitpick: Drop the comma on the sentinel.
+};
+
+MODULE_DEVICE_TABLE(of, wcd_pinctrl_of_match);
Nitpick: Drop the newline between device table and match table.