2 * Copyright (C) 2015 Broadcom Corporation
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
14 #include <linux/bitops.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/of_device.h>
17 #include <linux/of_irq.h>
18 #include <linux/module.h>
19 #include <linux/basic_mmio_gpio.h>
21 #define GIO_BANK_SIZE 0x20
22 #define GIO_ODEN(bank) (((bank) * GIO_BANK_SIZE) + 0x00)
23 #define GIO_DATA(bank) (((bank) * GIO_BANK_SIZE) + 0x04)
24 #define GIO_IODIR(bank) (((bank) * GIO_BANK_SIZE) + 0x08)
25 #define GIO_EC(bank) (((bank) * GIO_BANK_SIZE) + 0x0c)
26 #define GIO_EI(bank) (((bank) * GIO_BANK_SIZE) + 0x10)
27 #define GIO_MASK(bank) (((bank) * GIO_BANK_SIZE) + 0x14)
28 #define GIO_LEVEL(bank) (((bank) * GIO_BANK_SIZE) + 0x18)
29 #define GIO_STAT(bank) (((bank) * GIO_BANK_SIZE) + 0x1c)
31 struct brcmstb_gpio_bank {
32 struct list_head node;
34 struct bgpio_chip bgc;
35 struct brcmstb_gpio_priv *parent_priv;
39 struct brcmstb_gpio_priv {
40 struct list_head bank_list;
41 void __iomem *reg_base;
43 struct platform_device *pdev;
47 #define MAX_GPIO_PER_BANK 32
48 #define GPIO_BANK(gpio) ((gpio) >> 5)
49 /* assumes MAX_GPIO_PER_BANK is a multiple of 2 */
50 #define GPIO_BIT(gpio) ((gpio) & (MAX_GPIO_PER_BANK - 1))
52 static inline struct brcmstb_gpio_bank *
53 brcmstb_gpio_gc_to_bank(struct gpio_chip *gc)
55 struct bgpio_chip *bgc = to_bgpio_chip(gc);
56 return container_of(bgc, struct brcmstb_gpio_bank, bgc);
59 static inline struct brcmstb_gpio_priv *
60 brcmstb_gpio_gc_to_priv(struct gpio_chip *gc)
62 struct brcmstb_gpio_bank *bank = brcmstb_gpio_gc_to_bank(gc);
63 return bank->parent_priv;
66 /* Make sure that the number of banks matches up between properties */
67 static int brcmstb_gpio_sanity_check_banks(struct device *dev,
68 struct device_node *np, struct resource *res)
70 int res_num_banks = resource_size(res) / GIO_BANK_SIZE;
72 of_property_count_u32_elems(np, "brcm,gpio-bank-widths");
74 if (res_num_banks != num_banks) {
75 dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n",
76 res_num_banks, num_banks);
83 static int brcmstb_gpio_remove(struct platform_device *pdev)
85 struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev);
86 struct list_head *pos;
87 struct brcmstb_gpio_bank *bank;
91 dev_err(&pdev->dev, "called %s without drvdata!\n", __func__);
96 * You can lose return values below, but we report all errors, and it's
97 * more important to actually perform all of the steps.
99 list_for_each(pos, &priv->bank_list) {
100 bank = list_entry(pos, struct brcmstb_gpio_bank, node);
101 ret = bgpio_remove(&bank->bgc);
103 dev_err(&pdev->dev, "gpiochip_remove fail in cleanup");
108 static int brcmstb_gpio_of_xlate(struct gpio_chip *gc,
109 const struct of_phandle_args *gpiospec, u32 *flags)
111 struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
112 struct brcmstb_gpio_bank *bank = brcmstb_gpio_gc_to_bank(gc);
115 if (gc->of_gpio_n_cells != 2) {
120 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
123 offset = gpiospec->args[0] - (gc->base - priv->gpio_base);
124 if (offset >= gc->ngpio)
127 if (unlikely(offset >= bank->width)) {
128 dev_warn_ratelimited(&priv->pdev->dev,
129 "Received request for invalid GPIO offset %d\n",
134 *flags = gpiospec->args[1];
139 static int brcmstb_gpio_probe(struct platform_device *pdev)
141 struct device *dev = &pdev->dev;
142 struct device_node *np = dev->of_node;
143 void __iomem *reg_base;
144 struct brcmstb_gpio_priv *priv;
145 struct resource *res;
146 struct property *prop;
150 static int gpio_base;
152 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
155 platform_set_drvdata(pdev, priv);
156 INIT_LIST_HEAD(&priv->bank_list);
158 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
159 reg_base = devm_ioremap_resource(dev, res);
160 if (IS_ERR(reg_base))
161 return PTR_ERR(reg_base);
163 priv->gpio_base = gpio_base;
164 priv->reg_base = reg_base;
167 if (brcmstb_gpio_sanity_check_banks(dev, np, res))
170 of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p,
172 struct brcmstb_gpio_bank *bank;
173 struct bgpio_chip *bgc;
174 struct gpio_chip *gc;
176 bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
182 bank->parent_priv = priv;
183 bank->id = priv->num_banks;
184 if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) {
185 dev_err(dev, "Invalid bank width %d\n", bank_width);
188 bank->width = bank_width;
192 * Regs are 4 bytes wide, have data reg, no set/clear regs,
193 * and direction bits have 0 = output and 1 = input
196 err = bgpio_init(bgc, dev, 4,
197 reg_base + GIO_DATA(bank->id),
199 reg_base + GIO_IODIR(bank->id), 0);
201 dev_err(dev, "bgpio_init() failed\n");
207 gc->owner = THIS_MODULE;
208 gc->label = np->full_name;
209 gc->base = gpio_base;
210 gc->of_gpio_n_cells = 2;
211 gc->of_xlate = brcmstb_gpio_of_xlate;
212 /* not all ngpio lines are valid, will use bank width later */
213 gc->ngpio = MAX_GPIO_PER_BANK;
215 err = gpiochip_add(gc);
217 dev_err(dev, "Could not add gpiochip for bank %d\n",
221 gpio_base += gc->ngpio;
222 dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id,
223 gc->base, gc->ngpio, bank->width);
225 /* Everything looks good, so add bank to list */
226 list_add(&bank->node, &priv->bank_list);
231 dev_info(dev, "Registered %d banks (GPIO(s): %d-%d)\n",
232 priv->num_banks, priv->gpio_base, gpio_base - 1);
237 (void) brcmstb_gpio_remove(pdev);
241 static const struct of_device_id brcmstb_gpio_of_match[] = {
242 { .compatible = "brcm,brcmstb-gpio" },
246 MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match);
248 static struct platform_driver brcmstb_gpio_driver = {
250 .name = "brcmstb-gpio",
251 .of_match_table = brcmstb_gpio_of_match,
253 .probe = brcmstb_gpio_probe,
254 .remove = brcmstb_gpio_remove,
256 module_platform_driver(brcmstb_gpio_driver);
258 MODULE_AUTHOR("Gregory Fong");
259 MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO");
260 MODULE_LICENSE("GPL v2");