cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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gpio-wm831x.c (7447B)


      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * gpiolib support for Wolfson WM831x PMICs
      4 *
      5 * Copyright 2009 Wolfson Microelectronics PLC.
      6 *
      7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
      8 *
      9 */
     10
     11#include <linux/kernel.h>
     12#include <linux/slab.h>
     13#include <linux/module.h>
     14#include <linux/gpio/driver.h>
     15#include <linux/mfd/core.h>
     16#include <linux/platform_device.h>
     17#include <linux/seq_file.h>
     18
     19#include <linux/mfd/wm831x/core.h>
     20#include <linux/mfd/wm831x/pdata.h>
     21#include <linux/mfd/wm831x/gpio.h>
     22#include <linux/mfd/wm831x/irq.h>
     23
     24struct wm831x_gpio {
     25	struct wm831x *wm831x;
     26	struct gpio_chip gpio_chip;
     27};
     28
     29static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
     30{
     31	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
     32	struct wm831x *wm831x = wm831x_gpio->wm831x;
     33	int val = WM831X_GPN_DIR;
     34
     35	if (wm831x->has_gpio_ena)
     36		val |= WM831X_GPN_TRI;
     37
     38	return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
     39			       WM831X_GPN_DIR | WM831X_GPN_TRI |
     40			       WM831X_GPN_FN_MASK, val);
     41}
     42
     43static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
     44{
     45	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
     46	struct wm831x *wm831x = wm831x_gpio->wm831x;
     47	int ret;
     48
     49	ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
     50	if (ret < 0)
     51		return ret;
     52
     53	if (ret & 1 << offset)
     54		return 1;
     55	else
     56		return 0;
     57}
     58
     59static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
     60{
     61	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
     62	struct wm831x *wm831x = wm831x_gpio->wm831x;
     63
     64	wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
     65			value << offset);
     66}
     67
     68static int wm831x_gpio_direction_out(struct gpio_chip *chip,
     69				     unsigned offset, int value)
     70{
     71	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
     72	struct wm831x *wm831x = wm831x_gpio->wm831x;
     73	int val = 0;
     74	int ret;
     75
     76	if (wm831x->has_gpio_ena)
     77		val |= WM831X_GPN_TRI;
     78
     79	ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
     80			      WM831X_GPN_DIR | WM831X_GPN_TRI |
     81			      WM831X_GPN_FN_MASK, val);
     82	if (ret < 0)
     83		return ret;
     84
     85	/* Can only set GPIO state once it's in output mode */
     86	wm831x_gpio_set(chip, offset, value);
     87
     88	return 0;
     89}
     90
     91static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
     92{
     93	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
     94	struct wm831x *wm831x = wm831x_gpio->wm831x;
     95
     96	return irq_create_mapping(wm831x->irq_domain,
     97				  WM831X_IRQ_GPIO_1 + offset);
     98}
     99
    100static int wm831x_gpio_set_debounce(struct wm831x *wm831x, unsigned offset,
    101				    unsigned debounce)
    102{
    103	int reg = WM831X_GPIO1_CONTROL + offset;
    104	int ret, fn;
    105
    106	ret = wm831x_reg_read(wm831x, reg);
    107	if (ret < 0)
    108		return ret;
    109
    110	switch (ret & WM831X_GPN_FN_MASK) {
    111	case 0:
    112	case 1:
    113		break;
    114	default:
    115		/* Not in GPIO mode */
    116		return -EBUSY;
    117	}
    118
    119	if (debounce >= 32 && debounce <= 64)
    120		fn = 0;
    121	else if (debounce >= 4000 && debounce <= 8000)
    122		fn = 1;
    123	else
    124		return -EINVAL;
    125
    126	return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
    127}
    128
    129static int wm831x_set_config(struct gpio_chip *chip, unsigned int offset,
    130			     unsigned long config)
    131{
    132	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
    133	struct wm831x *wm831x = wm831x_gpio->wm831x;
    134	int reg = WM831X_GPIO1_CONTROL + offset;
    135
    136	switch (pinconf_to_config_param(config)) {
    137	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
    138		return wm831x_set_bits(wm831x, reg,
    139				       WM831X_GPN_OD_MASK, WM831X_GPN_OD);
    140	case PIN_CONFIG_DRIVE_PUSH_PULL:
    141		return wm831x_set_bits(wm831x, reg,
    142				       WM831X_GPN_OD_MASK, 0);
    143	case PIN_CONFIG_INPUT_DEBOUNCE:
    144		return wm831x_gpio_set_debounce(wm831x, offset,
    145			pinconf_to_config_argument(config));
    146	default:
    147		break;
    148	}
    149
    150	return -ENOTSUPP;
    151}
    152
    153#ifdef CONFIG_DEBUG_FS
    154static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
    155{
    156	struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
    157	struct wm831x *wm831x = wm831x_gpio->wm831x;
    158	int i, tristated;
    159
    160	for (i = 0; i < chip->ngpio; i++) {
    161		int gpio = i + chip->base;
    162		int reg;
    163		const char *label, *pull, *powerdomain;
    164
    165		/* We report the GPIO even if it's not requested since
    166		 * we're also reporting things like alternate
    167		 * functions which apply even when the GPIO is not in
    168		 * use as a GPIO.
    169		 */
    170		label = gpiochip_is_requested(chip, i);
    171		if (!label)
    172			label = "Unrequested";
    173
    174		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
    175
    176		reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
    177		if (reg < 0) {
    178			dev_err(wm831x->dev,
    179				"GPIO control %d read failed: %d\n",
    180				gpio, reg);
    181			seq_putc(s, '\n');
    182			continue;
    183		}
    184
    185		switch (reg & WM831X_GPN_PULL_MASK) {
    186		case WM831X_GPIO_PULL_NONE:
    187			pull = "nopull";
    188			break;
    189		case WM831X_GPIO_PULL_DOWN:
    190			pull = "pulldown";
    191			break;
    192		case WM831X_GPIO_PULL_UP:
    193			pull = "pullup";
    194			break;
    195		default:
    196			pull = "INVALID PULL";
    197			break;
    198		}
    199
    200		switch (i + 1) {
    201		case 1 ... 3:
    202		case 7 ... 9:
    203			if (reg & WM831X_GPN_PWR_DOM)
    204				powerdomain = "VPMIC";
    205			else
    206				powerdomain = "DBVDD";
    207			break;
    208
    209		case 4 ... 6:
    210		case 10 ... 12:
    211			if (reg & WM831X_GPN_PWR_DOM)
    212				powerdomain = "SYSVDD";
    213			else
    214				powerdomain = "DBVDD";
    215			break;
    216
    217		case 13 ... 16:
    218			powerdomain = "TPVDD";
    219			break;
    220
    221		default:
    222			BUG();
    223			break;
    224		}
    225
    226		tristated = reg & WM831X_GPN_TRI;
    227		if (wm831x->has_gpio_ena)
    228			tristated = !tristated;
    229
    230		seq_printf(s, " %s %s %s %s%s\n"
    231			   "                                  %s%s (0x%4x)\n",
    232			   reg & WM831X_GPN_DIR ? "in" : "out",
    233			   wm831x_gpio_get(chip, i) ? "high" : "low",
    234			   pull,
    235			   powerdomain,
    236			   reg & WM831X_GPN_POL ? "" : " inverted",
    237			   reg & WM831X_GPN_OD ? "open-drain" : "push-pull",
    238			   tristated ? " tristated" : "",
    239			   reg);
    240	}
    241}
    242#else
    243#define wm831x_gpio_dbg_show NULL
    244#endif
    245
    246static const struct gpio_chip template_chip = {
    247	.label			= "wm831x",
    248	.owner			= THIS_MODULE,
    249	.direction_input	= wm831x_gpio_direction_in,
    250	.get			= wm831x_gpio_get,
    251	.direction_output	= wm831x_gpio_direction_out,
    252	.set			= wm831x_gpio_set,
    253	.to_irq			= wm831x_gpio_to_irq,
    254	.set_config		= wm831x_set_config,
    255	.dbg_show		= wm831x_gpio_dbg_show,
    256	.can_sleep		= true,
    257};
    258
    259static int wm831x_gpio_probe(struct platform_device *pdev)
    260{
    261	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
    262	struct wm831x_pdata *pdata = &wm831x->pdata;
    263	struct wm831x_gpio *wm831x_gpio;
    264
    265	device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));
    266
    267	wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),
    268				   GFP_KERNEL);
    269	if (wm831x_gpio == NULL)
    270		return -ENOMEM;
    271
    272	wm831x_gpio->wm831x = wm831x;
    273	wm831x_gpio->gpio_chip = template_chip;
    274	wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;
    275	wm831x_gpio->gpio_chip.parent = &pdev->dev;
    276	if (pdata && pdata->gpio_base)
    277		wm831x_gpio->gpio_chip.base = pdata->gpio_base;
    278	else
    279		wm831x_gpio->gpio_chip.base = -1;
    280
    281	return devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip, wm831x_gpio);
    282}
    283
    284static struct platform_driver wm831x_gpio_driver = {
    285	.driver.name	= "wm831x-gpio",
    286	.probe		= wm831x_gpio_probe,
    287};
    288
    289static int __init wm831x_gpio_init(void)
    290{
    291	return platform_driver_register(&wm831x_gpio_driver);
    292}
    293subsys_initcall(wm831x_gpio_init);
    294
    295static void __exit wm831x_gpio_exit(void)
    296{
    297	platform_driver_unregister(&wm831x_gpio_driver);
    298}
    299module_exit(wm831x_gpio_exit);
    300
    301MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
    302MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
    303MODULE_LICENSE("GPL");
    304MODULE_ALIAS("platform:wm831x-gpio");