2 * AppliedMicro X-Gene SoC GPIO-Standby Driver
4 * Copyright (c) 2014, Applied Micro Circuits Corporation
5 * Author: Tin Huynh <tnhuynh@apm.com>.
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/of_gpio.h>
26 #include <linux/gpio/driver.h>
27 #include <linux/acpi.h>
31 #define XGENE_MAX_GPIO_DS 22
32 #define XGENE_MAX_GPIO_DS_IRQ 6
34 #define GPIO_MASK(x) (1U << ((x) % 32))
36 #define MPA_GPIO_INT_LVL 0x0290
37 #define MPA_GPIO_OE_ADDR 0x029c
38 #define MPA_GPIO_OUT_ADDR 0x02a0
39 #define MPA_GPIO_IN_ADDR 0x02a4
40 #define MPA_GPIO_SEL_LO 0x0294
43 * struct xgene_gpio_sb - GPIO-Standby private data structure.
44 * @gc: memory-mapped GPIO controllers.
45 * @irq: Mapping GPIO pins and interrupt number
46 * nirq: Number of GPIO pins that supports interrupt
48 struct xgene_gpio_sb
{
54 static void xgene_gpio_set_bit(struct gpio_chip
*gc
, void __iomem
*reg
, u32 gpio
, int val
)
58 data
= gc
->read_reg(reg
);
60 data
|= GPIO_MASK(gpio
);
62 data
&= ~GPIO_MASK(gpio
);
63 gc
->write_reg(reg
, data
);
66 static int apm_gpio_sb_to_irq(struct gpio_chip
*gc
, u32 gpio
)
68 struct xgene_gpio_sb
*priv
= gpiochip_get_data(gc
);
71 return priv
->irq
[gpio
];
76 static int xgene_gpio_sb_probe(struct platform_device
*pdev
)
78 struct xgene_gpio_sb
*priv
;
80 u32 default_lines
[] = {0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D};
84 priv
= devm_kzalloc(&pdev
->dev
, sizeof(*priv
), GFP_KERNEL
);
88 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
89 regs
= devm_ioremap_resource(&pdev
->dev
, res
);
93 ret
= bgpio_init(&priv
->gc
, &pdev
->dev
, 4,
94 regs
+ MPA_GPIO_IN_ADDR
,
95 regs
+ MPA_GPIO_OUT_ADDR
, NULL
,
96 regs
+ MPA_GPIO_OE_ADDR
, NULL
, 0);
100 priv
->gc
.to_irq
= apm_gpio_sb_to_irq
;
101 priv
->gc
.ngpio
= XGENE_MAX_GPIO_DS
;
103 priv
->nirq
= XGENE_MAX_GPIO_DS_IRQ
;
105 priv
->irq
= devm_kzalloc(&pdev
->dev
, sizeof(u32
) * XGENE_MAX_GPIO_DS
,
110 for (i
= 0; i
< priv
->nirq
; i
++) {
111 priv
->irq
[default_lines
[i
]] = platform_get_irq(pdev
, i
);
112 xgene_gpio_set_bit(&priv
->gc
, regs
+ MPA_GPIO_SEL_LO
,
113 default_lines
[i
] * 2, 1);
114 xgene_gpio_set_bit(&priv
->gc
, regs
+ MPA_GPIO_INT_LVL
, i
, 1);
117 platform_set_drvdata(pdev
, priv
);
119 ret
= gpiochip_add_data(&priv
->gc
, priv
);
121 dev_err(&pdev
->dev
, "failed to register X-Gene GPIO Standby driver\n");
123 dev_info(&pdev
->dev
, "X-Gene GPIO Standby driver registered\n");
125 if (priv
->nirq
> 0) {
126 /* Register interrupt handlers for gpio signaled acpi events */
127 acpi_gpiochip_request_interrupts(&priv
->gc
);
133 static int xgene_gpio_sb_remove(struct platform_device
*pdev
)
135 struct xgene_gpio_sb
*priv
= platform_get_drvdata(pdev
);
137 if (priv
->nirq
> 0) {
138 acpi_gpiochip_free_interrupts(&priv
->gc
);
141 gpiochip_remove(&priv
->gc
);
145 static const struct of_device_id xgene_gpio_sb_of_match
[] = {
146 {.compatible
= "apm,xgene-gpio-sb", },
149 MODULE_DEVICE_TABLE(of
, xgene_gpio_sb_of_match
);
152 static const struct acpi_device_id xgene_gpio_sb_acpi_match
[] = {
156 MODULE_DEVICE_TABLE(acpi
, xgene_gpio_sb_acpi_match
);
159 static struct platform_driver xgene_gpio_sb_driver
= {
161 .name
= "xgene-gpio-sb",
162 .of_match_table
= xgene_gpio_sb_of_match
,
163 .acpi_match_table
= ACPI_PTR(xgene_gpio_sb_acpi_match
),
165 .probe
= xgene_gpio_sb_probe
,
166 .remove
= xgene_gpio_sb_remove
,
168 module_platform_driver(xgene_gpio_sb_driver
);
170 MODULE_AUTHOR("AppliedMicro");
171 MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver");
172 MODULE_LICENSE("GPL");