1 /*
2 * This program is free software; you can redistribute it and/or modify it
3 * under the terms of the GNU General Public License version 2 as published
4 * by the Free Software Foundation.
5 *
6 * Copyright (C) 2007 John Crispin <blogic@openwrt.org>
7 *
8 */
9
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/export.h>
13 #include <linux/types.h>
14 #include <linux/platform_device.h>
15 #include <linux/mutex.h>
16 #include <linux/io.h>
17 #include <linux/gpio.h>
18
19 #include <lantiq_soc.h>
20
21 #define LTQ_STP_CON0 0x00
22 #define LTQ_STP_CON1 0x04
23 #define LTQ_STP_CPU0 0x08
24 #define LTQ_STP_CPU1 0x0C
25 #define LTQ_STP_AR 0x10
26
27 #define LTQ_STP_CON_SWU (1 << 31)
28 #define LTQ_STP_2HZ 0
29 #define LTQ_STP_4HZ (1 << 23)
30 #define LTQ_STP_8HZ (2 << 23)
31 #define LTQ_STP_10HZ (3 << 23)
32 #define LTQ_STP_SPEED_MASK (0xf << 23)
33 #define LTQ_STP_UPD_FPI (1 << 31)
34 #define LTQ_STP_UPD_MASK (3 << 30)
35 #define LTQ_STP_ADSL_SRC (3 << 24)
36
37 #define LTQ_STP_GROUP0 (1 << 0)
38
39 #define LTQ_STP_RISING 0
40 #define LTQ_STP_FALLING (1 << 26)
41 #define LTQ_STP_EDGE_MASK (1 << 26)
42
43 #define ltq_stp_r32(reg) __raw_readl(ltq_stp_membase + reg)
44 #define ltq_stp_w32(val, reg) __raw_writel(val, ltq_stp_membase + reg)
45 #define ltq_stp_w32_mask(clear, set, reg) \
46 ltq_w32((ltq_r32(ltq_stp_membase + reg) & ~(clear)) | (set), \
47 ltq_stp_membase + (reg))
48
49 static int ltq_stp_shadow = 0xffff;
50 static void __iomem *ltq_stp_membase;
51
ltq_stp_set(struct gpio_chip * chip,unsigned offset,int value)52 static void ltq_stp_set(struct gpio_chip *chip, unsigned offset, int value)
53 {
54 if (value)
55 ltq_stp_shadow |= (1 << offset);
56 else
57 ltq_stp_shadow &= ~(1 << offset);
58 ltq_stp_w32(ltq_stp_shadow, LTQ_STP_CPU0);
59 }
60
ltq_stp_direction_output(struct gpio_chip * chip,unsigned offset,int value)61 static int ltq_stp_direction_output(struct gpio_chip *chip, unsigned offset,
62 int value)
63 {
64 ltq_stp_set(chip, offset, value);
65
66 return 0;
67 }
68
69 static struct gpio_chip ltq_stp_chip = {
70 .label = "ltq_stp",
71 .direction_output = ltq_stp_direction_output,
72 .set = ltq_stp_set,
73 .base = 48,
74 .ngpio = 24,
75 .can_sleep = 1,
76 .owner = THIS_MODULE,
77 };
78
ltq_stp_hw_init(void)79 static int ltq_stp_hw_init(void)
80 {
81 /* the 3 pins used to control the external stp */
82 ltq_gpio_request(4, 1, 0, 1, "stp-st");
83 ltq_gpio_request(5, 1, 0, 1, "stp-d");
84 ltq_gpio_request(6, 1, 0, 1, "stp-sh");
85
86 /* sane defaults */
87 ltq_stp_w32(0, LTQ_STP_AR);
88 ltq_stp_w32(0, LTQ_STP_CPU0);
89 ltq_stp_w32(0, LTQ_STP_CPU1);
90 ltq_stp_w32(LTQ_STP_CON_SWU, LTQ_STP_CON0);
91 ltq_stp_w32(0, LTQ_STP_CON1);
92
93 /* rising or falling edge */
94 ltq_stp_w32_mask(LTQ_STP_EDGE_MASK, LTQ_STP_FALLING, LTQ_STP_CON0);
95
96 /* per default stp 15-0 are set */
97 ltq_stp_w32_mask(0, LTQ_STP_GROUP0, LTQ_STP_CON1);
98
99 /* stp are update periodically by the FPI bus */
100 ltq_stp_w32_mask(LTQ_STP_UPD_MASK, LTQ_STP_UPD_FPI, LTQ_STP_CON1);
101
102 /* set stp update speed */
103 ltq_stp_w32_mask(LTQ_STP_SPEED_MASK, LTQ_STP_8HZ, LTQ_STP_CON1);
104
105 /* tell the hardware that pin (led) 0 and 1 are controlled
106 * by the dsl arc
107 */
108 ltq_stp_w32_mask(0, LTQ_STP_ADSL_SRC, LTQ_STP_CON0);
109
110 ltq_pmu_enable(PMU_LED);
111 return 0;
112 }
113
ltq_stp_probe(struct platform_device * pdev)114 static int __devinit ltq_stp_probe(struct platform_device *pdev)
115 {
116 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
117 int ret = 0;
118
119 if (!res)
120 return -ENOENT;
121 res = devm_request_mem_region(&pdev->dev, res->start,
122 resource_size(res), dev_name(&pdev->dev));
123 if (!res) {
124 dev_err(&pdev->dev, "failed to request STP memory\n");
125 return -EBUSY;
126 }
127 ltq_stp_membase = devm_ioremap_nocache(&pdev->dev, res->start,
128 resource_size(res));
129 if (!ltq_stp_membase) {
130 dev_err(&pdev->dev, "failed to remap STP memory\n");
131 return -ENOMEM;
132 }
133 ret = gpiochip_add(<q_stp_chip);
134 if (!ret)
135 ret = ltq_stp_hw_init();
136
137 return ret;
138 }
139
140 static struct platform_driver ltq_stp_driver = {
141 .probe = ltq_stp_probe,
142 .driver = {
143 .name = "ltq_stp",
144 .owner = THIS_MODULE,
145 },
146 };
147
ltq_stp_init(void)148 int __init ltq_stp_init(void)
149 {
150 int ret = platform_driver_register(<q_stp_driver);
151
152 if (ret)
153 pr_info("ltq_stp: error registering platfom driver");
154 return ret;
155 }
156
157 postcore_initcall(ltq_stp_init);
158