Loading...
1/*
2 * GPIO interface for Intel Poulsbo SCH
3 *
4 * Copyright (c) 2010 CompuLab Ltd
5 * Author: Denis Turischev <denis@compulab.co.il>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License 2 as published
9 * by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; see the file COPYING. If not, write to
18 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/io.h>
25#include <linux/errno.h>
26#include <linux/acpi.h>
27#include <linux/platform_device.h>
28#include <linux/pci_ids.h>
29
30#include <linux/gpio.h>
31
32#define GEN 0x00
33#define GIO 0x04
34#define GLV 0x08
35
36struct sch_gpio {
37 struct gpio_chip chip;
38 spinlock_t lock;
39 unsigned short iobase;
40 unsigned short core_base;
41 unsigned short resume_base;
42};
43
44static unsigned sch_gpio_offset(struct sch_gpio *sch, unsigned gpio,
45 unsigned reg)
46{
47 unsigned base = 0;
48
49 if (gpio >= sch->resume_base) {
50 gpio -= sch->resume_base;
51 base += 0x20;
52 }
53
54 return base + reg + gpio / 8;
55}
56
57static unsigned sch_gpio_bit(struct sch_gpio *sch, unsigned gpio)
58{
59 if (gpio >= sch->resume_base)
60 gpio -= sch->resume_base;
61 return gpio % 8;
62}
63
64static int sch_gpio_reg_get(struct sch_gpio *sch, unsigned gpio, unsigned reg)
65{
66 unsigned short offset, bit;
67 u8 reg_val;
68
69 offset = sch_gpio_offset(sch, gpio, reg);
70 bit = sch_gpio_bit(sch, gpio);
71
72 reg_val = !!(inb(sch->iobase + offset) & BIT(bit));
73
74 return reg_val;
75}
76
77static void sch_gpio_reg_set(struct sch_gpio *sch, unsigned gpio, unsigned reg,
78 int val)
79{
80 unsigned short offset, bit;
81 u8 reg_val;
82
83 offset = sch_gpio_offset(sch, gpio, reg);
84 bit = sch_gpio_bit(sch, gpio);
85
86 reg_val = inb(sch->iobase + offset);
87
88 if (val)
89 outb(reg_val | BIT(bit), sch->iobase + offset);
90 else
91 outb((reg_val & ~BIT(bit)), sch->iobase + offset);
92}
93
94static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num)
95{
96 struct sch_gpio *sch = gpiochip_get_data(gc);
97
98 spin_lock(&sch->lock);
99 sch_gpio_reg_set(sch, gpio_num, GIO, 1);
100 spin_unlock(&sch->lock);
101 return 0;
102}
103
104static int sch_gpio_get(struct gpio_chip *gc, unsigned gpio_num)
105{
106 struct sch_gpio *sch = gpiochip_get_data(gc);
107 return sch_gpio_reg_get(sch, gpio_num, GLV);
108}
109
110static void sch_gpio_set(struct gpio_chip *gc, unsigned gpio_num, int val)
111{
112 struct sch_gpio *sch = gpiochip_get_data(gc);
113
114 spin_lock(&sch->lock);
115 sch_gpio_reg_set(sch, gpio_num, GLV, val);
116 spin_unlock(&sch->lock);
117}
118
119static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned gpio_num,
120 int val)
121{
122 struct sch_gpio *sch = gpiochip_get_data(gc);
123
124 spin_lock(&sch->lock);
125 sch_gpio_reg_set(sch, gpio_num, GIO, 0);
126 spin_unlock(&sch->lock);
127
128 /*
129 * according to the datasheet, writing to the level register has no
130 * effect when GPIO is programmed as input.
131 * Actually the the level register is read-only when configured as input.
132 * Thus presetting the output level before switching to output is _NOT_ possible.
133 * Hence we set the level after configuring the GPIO as output.
134 * But we cannot prevent a short low pulse if direction is set to high
135 * and an external pull-up is connected.
136 */
137 sch_gpio_set(gc, gpio_num, val);
138 return 0;
139}
140
141static const struct gpio_chip sch_gpio_chip = {
142 .label = "sch_gpio",
143 .owner = THIS_MODULE,
144 .direction_input = sch_gpio_direction_in,
145 .get = sch_gpio_get,
146 .direction_output = sch_gpio_direction_out,
147 .set = sch_gpio_set,
148};
149
150static int sch_gpio_probe(struct platform_device *pdev)
151{
152 struct sch_gpio *sch;
153 struct resource *res;
154
155 sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
156 if (!sch)
157 return -ENOMEM;
158
159 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
160 if (!res)
161 return -EBUSY;
162
163 if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
164 pdev->name))
165 return -EBUSY;
166
167 spin_lock_init(&sch->lock);
168 sch->iobase = res->start;
169 sch->chip = sch_gpio_chip;
170 sch->chip.label = dev_name(&pdev->dev);
171 sch->chip.parent = &pdev->dev;
172
173 switch (pdev->id) {
174 case PCI_DEVICE_ID_INTEL_SCH_LPC:
175 sch->core_base = 0;
176 sch->resume_base = 10;
177 sch->chip.ngpio = 14;
178
179 /*
180 * GPIO[6:0] enabled by default
181 * GPIO7 is configured by the CMC as SLPIOVR
182 * Enable GPIO[9:8] core powered gpios explicitly
183 */
184 sch_gpio_reg_set(sch, 8, GEN, 1);
185 sch_gpio_reg_set(sch, 9, GEN, 1);
186 /*
187 * SUS_GPIO[2:0] enabled by default
188 * Enable SUS_GPIO3 resume powered gpio explicitly
189 */
190 sch_gpio_reg_set(sch, 13, GEN, 1);
191 break;
192
193 case PCI_DEVICE_ID_INTEL_ITC_LPC:
194 sch->core_base = 0;
195 sch->resume_base = 5;
196 sch->chip.ngpio = 14;
197 break;
198
199 case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
200 sch->core_base = 0;
201 sch->resume_base = 21;
202 sch->chip.ngpio = 30;
203 break;
204
205 case PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB:
206 sch->core_base = 0;
207 sch->resume_base = 2;
208 sch->chip.ngpio = 8;
209 break;
210
211 default:
212 return -ENODEV;
213 }
214
215 platform_set_drvdata(pdev, sch);
216
217 return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch);
218}
219
220static struct platform_driver sch_gpio_driver = {
221 .driver = {
222 .name = "sch_gpio",
223 },
224 .probe = sch_gpio_probe,
225};
226
227module_platform_driver(sch_gpio_driver);
228
229MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
230MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
231MODULE_LICENSE("GPL");
232MODULE_ALIAS("platform:sch_gpio");
1/*
2 * GPIO interface for Intel Poulsbo SCH
3 *
4 * Copyright (c) 2010 CompuLab Ltd
5 * Author: Denis Turischev <denis@compulab.co.il>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License 2 as published
9 * by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; see the file COPYING. If not, write to
18 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21#include <linux/init.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/io.h>
25#include <linux/errno.h>
26#include <linux/acpi.h>
27#include <linux/platform_device.h>
28#include <linux/pci_ids.h>
29
30#include <linux/gpio.h>
31
32#define GEN 0x00
33#define GIO 0x04
34#define GLV 0x08
35
36struct sch_gpio {
37 struct gpio_chip chip;
38 spinlock_t lock;
39 unsigned short iobase;
40 unsigned short core_base;
41 unsigned short resume_base;
42};
43
44static unsigned sch_gpio_offset(struct sch_gpio *sch, unsigned gpio,
45 unsigned reg)
46{
47 unsigned base = 0;
48
49 if (gpio >= sch->resume_base) {
50 gpio -= sch->resume_base;
51 base += 0x20;
52 }
53
54 return base + reg + gpio / 8;
55}
56
57static unsigned sch_gpio_bit(struct sch_gpio *sch, unsigned gpio)
58{
59 if (gpio >= sch->resume_base)
60 gpio -= sch->resume_base;
61 return gpio % 8;
62}
63
64static int sch_gpio_reg_get(struct sch_gpio *sch, unsigned gpio, unsigned reg)
65{
66 unsigned short offset, bit;
67 u8 reg_val;
68
69 offset = sch_gpio_offset(sch, gpio, reg);
70 bit = sch_gpio_bit(sch, gpio);
71
72 reg_val = !!(inb(sch->iobase + offset) & BIT(bit));
73
74 return reg_val;
75}
76
77static void sch_gpio_reg_set(struct sch_gpio *sch, unsigned gpio, unsigned reg,
78 int val)
79{
80 unsigned short offset, bit;
81 u8 reg_val;
82
83 offset = sch_gpio_offset(sch, gpio, reg);
84 bit = sch_gpio_bit(sch, gpio);
85
86 reg_val = inb(sch->iobase + offset);
87
88 if (val)
89 outb(reg_val | BIT(bit), sch->iobase + offset);
90 else
91 outb((reg_val & ~BIT(bit)), sch->iobase + offset);
92}
93
94static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num)
95{
96 struct sch_gpio *sch = gpiochip_get_data(gc);
97
98 spin_lock(&sch->lock);
99 sch_gpio_reg_set(sch, gpio_num, GIO, 1);
100 spin_unlock(&sch->lock);
101 return 0;
102}
103
104static int sch_gpio_get(struct gpio_chip *gc, unsigned gpio_num)
105{
106 struct sch_gpio *sch = gpiochip_get_data(gc);
107 return sch_gpio_reg_get(sch, gpio_num, GLV);
108}
109
110static void sch_gpio_set(struct gpio_chip *gc, unsigned gpio_num, int val)
111{
112 struct sch_gpio *sch = gpiochip_get_data(gc);
113
114 spin_lock(&sch->lock);
115 sch_gpio_reg_set(sch, gpio_num, GLV, val);
116 spin_unlock(&sch->lock);
117}
118
119static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned gpio_num,
120 int val)
121{
122 struct sch_gpio *sch = gpiochip_get_data(gc);
123
124 spin_lock(&sch->lock);
125 sch_gpio_reg_set(sch, gpio_num, GIO, 0);
126 spin_unlock(&sch->lock);
127
128 /*
129 * according to the datasheet, writing to the level register has no
130 * effect when GPIO is programmed as input.
131 * Actually the the level register is read-only when configured as input.
132 * Thus presetting the output level before switching to output is _NOT_ possible.
133 * Hence we set the level after configuring the GPIO as output.
134 * But we cannot prevent a short low pulse if direction is set to high
135 * and an external pull-up is connected.
136 */
137 sch_gpio_set(gc, gpio_num, val);
138 return 0;
139}
140
141static const struct gpio_chip sch_gpio_chip = {
142 .label = "sch_gpio",
143 .owner = THIS_MODULE,
144 .direction_input = sch_gpio_direction_in,
145 .get = sch_gpio_get,
146 .direction_output = sch_gpio_direction_out,
147 .set = sch_gpio_set,
148};
149
150static int sch_gpio_probe(struct platform_device *pdev)
151{
152 struct sch_gpio *sch;
153 struct resource *res;
154
155 sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
156 if (!sch)
157 return -ENOMEM;
158
159 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
160 if (!res)
161 return -EBUSY;
162
163 if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
164 pdev->name))
165 return -EBUSY;
166
167 spin_lock_init(&sch->lock);
168 sch->iobase = res->start;
169 sch->chip = sch_gpio_chip;
170 sch->chip.label = dev_name(&pdev->dev);
171 sch->chip.parent = &pdev->dev;
172
173 switch (pdev->id) {
174 case PCI_DEVICE_ID_INTEL_SCH_LPC:
175 sch->core_base = 0;
176 sch->resume_base = 10;
177 sch->chip.ngpio = 14;
178
179 /*
180 * GPIO[6:0] enabled by default
181 * GPIO7 is configured by the CMC as SLPIOVR
182 * Enable GPIO[9:8] core powered gpios explicitly
183 */
184 sch_gpio_reg_set(sch, 8, GEN, 1);
185 sch_gpio_reg_set(sch, 9, GEN, 1);
186 /*
187 * SUS_GPIO[2:0] enabled by default
188 * Enable SUS_GPIO3 resume powered gpio explicitly
189 */
190 sch_gpio_reg_set(sch, 13, GEN, 1);
191 break;
192
193 case PCI_DEVICE_ID_INTEL_ITC_LPC:
194 sch->core_base = 0;
195 sch->resume_base = 5;
196 sch->chip.ngpio = 14;
197 break;
198
199 case PCI_DEVICE_ID_INTEL_CENTERTON_ILB:
200 sch->core_base = 0;
201 sch->resume_base = 21;
202 sch->chip.ngpio = 30;
203 break;
204
205 case PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB:
206 sch->core_base = 0;
207 sch->resume_base = 2;
208 sch->chip.ngpio = 8;
209 break;
210
211 default:
212 return -ENODEV;
213 }
214
215 platform_set_drvdata(pdev, sch);
216
217 return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch);
218}
219
220static struct platform_driver sch_gpio_driver = {
221 .driver = {
222 .name = "sch_gpio",
223 },
224 .probe = sch_gpio_probe,
225};
226
227module_platform_driver(sch_gpio_driver);
228
229MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
230MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
231MODULE_LICENSE("GPL");
232MODULE_ALIAS("platform:sch_gpio");