xref: /openbmc/linux/drivers/mfd/tqmx86.c (revision e82c878d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * TQ-Systems PLD MFD core driver, based on vendor driver by
4  * Vadim V.Vlasov <vvlasov@dev.rtsoft.ru>
5  *
6  * Copyright (c) 2015 TQ-Systems GmbH
7  * Copyright (c) 2019 Andrew Lunn <andrew@lunn.ch>
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/dmi.h>
12 #include <linux/i2c.h>
13 #include <linux/io.h>
14 #include <linux/mfd/core.h>
15 #include <linux/module.h>
16 #include <linux/platform_data/i2c-ocores.h>
17 #include <linux/platform_device.h>
18 
19 #define TQMX86_IOBASE	0x160
20 #define TQMX86_IOSIZE	0x3f
21 #define TQMX86_IOBASE_I2C	0x1a0
22 #define TQMX86_IOSIZE_I2C	0xa
23 #define TQMX86_IOBASE_WATCHDOG	0x18b
24 #define TQMX86_IOSIZE_WATCHDOG	0x2
25 #define TQMX86_IOBASE_GPIO	0x18d
26 #define TQMX86_IOSIZE_GPIO	0x4
27 
28 #define TQMX86_REG_BOARD_ID	0x20
29 #define TQMX86_REG_BOARD_ID_E38M	1
30 #define TQMX86_REG_BOARD_ID_50UC	2
31 #define TQMX86_REG_BOARD_ID_E38C	3
32 #define TQMX86_REG_BOARD_ID_60EB	4
33 #define TQMX86_REG_BOARD_ID_E39M	5
34 #define TQMX86_REG_BOARD_ID_E39C	6
35 #define TQMX86_REG_BOARD_ID_E39x	7
36 #define TQMX86_REG_BOARD_ID_70EB	8
37 #define TQMX86_REG_BOARD_ID_80UC	9
38 #define TQMX86_REG_BOARD_ID_90UC	10
39 #define TQMX86_REG_BOARD_REV	0x21
40 #define TQMX86_REG_IO_EXT_INT	0x26
41 #define TQMX86_REG_IO_EXT_INT_NONE		0
42 #define TQMX86_REG_IO_EXT_INT_7			1
43 #define TQMX86_REG_IO_EXT_INT_9			2
44 #define TQMX86_REG_IO_EXT_INT_12		3
45 #define TQMX86_REG_IO_EXT_INT_MASK		0x3
46 #define TQMX86_REG_IO_EXT_INT_GPIO_SHIFT	4
47 
48 #define TQMX86_REG_I2C_DETECT	0x47
49 #define TQMX86_REG_I2C_DETECT_SOFT		0xa5
50 #define TQMX86_REG_I2C_INT_EN	0x49
51 
52 static uint gpio_irq;
53 module_param(gpio_irq, uint, 0);
54 MODULE_PARM_DESC(gpio_irq, "GPIO IRQ number (7, 9, 12)");
55 
56 static const struct resource tqmx_i2c_soft_resources[] = {
57 	DEFINE_RES_IO(TQMX86_IOBASE_I2C, TQMX86_IOSIZE_I2C),
58 };
59 
60 static const struct resource tqmx_watchdog_resources[] = {
61 	DEFINE_RES_IO(TQMX86_IOBASE_WATCHDOG, TQMX86_IOSIZE_WATCHDOG),
62 };
63 
64 /*
65  * The IRQ resource must be first, since it is updated with the
66  * configured IRQ in the probe function.
67  */
68 static struct resource tqmx_gpio_resources[] = {
69 	DEFINE_RES_IRQ(0),
70 	DEFINE_RES_IO(TQMX86_IOBASE_GPIO, TQMX86_IOSIZE_GPIO),
71 };
72 
73 static struct i2c_board_info tqmx86_i2c_devices[] = {
74 	{
75 		/* 4K EEPROM at 0x50 */
76 		I2C_BOARD_INFO("24c32", 0x50),
77 	},
78 };
79 
80 static struct ocores_i2c_platform_data ocores_platfom_data = {
81 	.num_devices = ARRAY_SIZE(tqmx86_i2c_devices),
82 	.devices = tqmx86_i2c_devices,
83 };
84 
85 static const struct mfd_cell tqmx86_i2c_soft_dev[] = {
86 	{
87 		.name = "ocores-i2c",
88 		.platform_data = &ocores_platfom_data,
89 		.pdata_size = sizeof(ocores_platfom_data),
90 		.resources = tqmx_i2c_soft_resources,
91 		.num_resources = ARRAY_SIZE(tqmx_i2c_soft_resources),
92 	},
93 };
94 
95 static const struct mfd_cell tqmx86_devs[] = {
96 	{
97 		.name = "tqmx86-wdt",
98 		.resources = tqmx_watchdog_resources,
99 		.num_resources = ARRAY_SIZE(tqmx_watchdog_resources),
100 		.ignore_resource_conflicts = true,
101 	},
102 	{
103 		.name = "tqmx86-gpio",
104 		.resources = tqmx_gpio_resources,
105 		.num_resources = ARRAY_SIZE(tqmx_gpio_resources),
106 		.ignore_resource_conflicts = true,
107 	},
108 };
109 
110 static const char *tqmx86_board_id_to_name(u8 board_id)
111 {
112 	switch (board_id) {
113 	case TQMX86_REG_BOARD_ID_E38M:
114 		return "TQMxE38M";
115 	case TQMX86_REG_BOARD_ID_50UC:
116 		return "TQMx50UC";
117 	case TQMX86_REG_BOARD_ID_E38C:
118 		return "TQMxE38C";
119 	case TQMX86_REG_BOARD_ID_60EB:
120 		return "TQMx60EB";
121 	case TQMX86_REG_BOARD_ID_E39M:
122 		return "TQMxE39M";
123 	case TQMX86_REG_BOARD_ID_E39C:
124 		return "TQMxE39C";
125 	case TQMX86_REG_BOARD_ID_E39x:
126 		return "TQMxE39x";
127 	case TQMX86_REG_BOARD_ID_70EB:
128 		return "TQMx70EB";
129 	case TQMX86_REG_BOARD_ID_80UC:
130 		return "TQMx80UC";
131 	case TQMX86_REG_BOARD_ID_90UC:
132 		return "TQMx90UC";
133 	default:
134 		return "Unknown";
135 	}
136 }
137 
138 static int tqmx86_board_id_to_clk_rate(u8 board_id)
139 {
140 	switch (board_id) {
141 	case TQMX86_REG_BOARD_ID_50UC:
142 	case TQMX86_REG_BOARD_ID_60EB:
143 	case TQMX86_REG_BOARD_ID_70EB:
144 	case TQMX86_REG_BOARD_ID_80UC:
145 	case TQMX86_REG_BOARD_ID_90UC:
146 		return 24000;
147 	case TQMX86_REG_BOARD_ID_E39M:
148 	case TQMX86_REG_BOARD_ID_E39C:
149 	case TQMX86_REG_BOARD_ID_E39x:
150 		return 25000;
151 	case TQMX86_REG_BOARD_ID_E38M:
152 	case TQMX86_REG_BOARD_ID_E38C:
153 		return 33000;
154 	default:
155 		return 0;
156 	}
157 }
158 
159 static int tqmx86_probe(struct platform_device *pdev)
160 {
161 	u8 board_id, rev, i2c_det, io_ext_int_val;
162 	struct device *dev = &pdev->dev;
163 	u8 gpio_irq_cfg, readback;
164 	const char *board_name;
165 	void __iomem *io_base;
166 	int err;
167 
168 	switch (gpio_irq) {
169 	case 0:
170 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_NONE;
171 		break;
172 	case 7:
173 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_7;
174 		break;
175 	case 9:
176 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_9;
177 		break;
178 	case 12:
179 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_12;
180 		break;
181 	default:
182 		pr_err("tqmx86: Invalid GPIO IRQ (%d)\n", gpio_irq);
183 		return -EINVAL;
184 	}
185 
186 	io_base = devm_ioport_map(dev, TQMX86_IOBASE, TQMX86_IOSIZE);
187 	if (!io_base)
188 		return -ENOMEM;
189 
190 	board_id = ioread8(io_base + TQMX86_REG_BOARD_ID);
191 	board_name = tqmx86_board_id_to_name(board_id);
192 	rev = ioread8(io_base + TQMX86_REG_BOARD_REV);
193 
194 	dev_info(dev,
195 		 "Found %s - Board ID %d, PCB Revision %d, PLD Revision %d\n",
196 		 board_name, board_id, rev >> 4, rev & 0xf);
197 
198 	i2c_det = ioread8(io_base + TQMX86_REG_I2C_DETECT);
199 
200 	if (gpio_irq_cfg) {
201 		io_ext_int_val =
202 			gpio_irq_cfg << TQMX86_REG_IO_EXT_INT_GPIO_SHIFT;
203 		iowrite8(io_ext_int_val, io_base + TQMX86_REG_IO_EXT_INT);
204 		readback = ioread8(io_base + TQMX86_REG_IO_EXT_INT);
205 		if (readback != io_ext_int_val) {
206 			dev_warn(dev, "GPIO interrupts not supported.\n");
207 			return -EINVAL;
208 		}
209 
210 		/* Assumes the IRQ resource is first. */
211 		tqmx_gpio_resources[0].start = gpio_irq;
212 	}
213 
214 	ocores_platfom_data.clock_khz = tqmx86_board_id_to_clk_rate(board_id);
215 
216 	if (i2c_det == TQMX86_REG_I2C_DETECT_SOFT) {
217 		err = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
218 					   tqmx86_i2c_soft_dev,
219 					   ARRAY_SIZE(tqmx86_i2c_soft_dev),
220 					   NULL, 0, NULL);
221 		if (err)
222 			return err;
223 	}
224 
225 	return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
226 				    tqmx86_devs,
227 				    ARRAY_SIZE(tqmx86_devs),
228 				    NULL, 0, NULL);
229 }
230 
231 static int tqmx86_create_platform_device(const struct dmi_system_id *id)
232 {
233 	struct platform_device *pdev;
234 	int err;
235 
236 	pdev = platform_device_alloc("tqmx86", -1);
237 	if (!pdev)
238 		return -ENOMEM;
239 
240 	err = platform_device_add(pdev);
241 	if (err)
242 		platform_device_put(pdev);
243 
244 	return err;
245 }
246 
247 static const struct dmi_system_id tqmx86_dmi_table[] __initconst = {
248 	{
249 		.ident = "TQMX86",
250 		.matches = {
251 			DMI_MATCH(DMI_SYS_VENDOR, "TQ-Group"),
252 			DMI_MATCH(DMI_PRODUCT_NAME, "TQMx"),
253 		},
254 		.callback = tqmx86_create_platform_device,
255 	},
256 	{}
257 };
258 MODULE_DEVICE_TABLE(dmi, tqmx86_dmi_table);
259 
260 static struct platform_driver tqmx86_driver = {
261 	.driver		= {
262 		.name	= "tqmx86",
263 	},
264 	.probe		= tqmx86_probe,
265 };
266 
267 static int __init tqmx86_init(void)
268 {
269 	if (!dmi_check_system(tqmx86_dmi_table))
270 		return -ENODEV;
271 
272 	return platform_driver_register(&tqmx86_driver);
273 }
274 
275 module_init(tqmx86_init);
276 
277 MODULE_DESCRIPTION("TQx86 PLD Core Driver");
278 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
279 MODULE_LICENSE("GPL");
280 MODULE_ALIAS("platform:tqmx86");
281