xref: /openbmc/linux/drivers/mfd/tqmx86.c (revision bc33f5e5)
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_110EB	11
39 #define TQMX86_REG_BOARD_ID_E40M	12
40 #define TQMX86_REG_BOARD_ID_E40S	13
41 #define TQMX86_REG_BOARD_ID_E40C1	14
42 #define TQMX86_REG_BOARD_ID_E40C2	15
43 #define TQMX86_REG_BOARD_REV	0x21
44 #define TQMX86_REG_IO_EXT_INT	0x26
45 #define TQMX86_REG_IO_EXT_INT_NONE		0
46 #define TQMX86_REG_IO_EXT_INT_7			1
47 #define TQMX86_REG_IO_EXT_INT_9			2
48 #define TQMX86_REG_IO_EXT_INT_12		3
49 #define TQMX86_REG_IO_EXT_INT_MASK		0x3
50 #define TQMX86_REG_IO_EXT_INT_GPIO_SHIFT	4
51 
52 #define TQMX86_REG_I2C_DETECT	0x47
53 #define TQMX86_REG_I2C_DETECT_SOFT		0xa5
54 #define TQMX86_REG_I2C_INT_EN	0x49
55 
56 static uint gpio_irq;
57 module_param(gpio_irq, uint, 0);
58 MODULE_PARM_DESC(gpio_irq, "GPIO IRQ number (7, 9, 12)");
59 
60 static const struct resource tqmx_i2c_soft_resources[] = {
61 	DEFINE_RES_IO(TQMX86_IOBASE_I2C, TQMX86_IOSIZE_I2C),
62 };
63 
64 static const struct resource tqmx_watchdog_resources[] = {
65 	DEFINE_RES_IO(TQMX86_IOBASE_WATCHDOG, TQMX86_IOSIZE_WATCHDOG),
66 };
67 
68 /*
69  * The IRQ resource must be first, since it is updated with the
70  * configured IRQ in the probe function.
71  */
72 static struct resource tqmx_gpio_resources[] = {
73 	DEFINE_RES_IRQ(0),
74 	DEFINE_RES_IO(TQMX86_IOBASE_GPIO, TQMX86_IOSIZE_GPIO),
75 };
76 
77 static struct i2c_board_info tqmx86_i2c_devices[] = {
78 	{
79 		/* 4K EEPROM at 0x50 */
80 		I2C_BOARD_INFO("24c32", 0x50),
81 	},
82 };
83 
84 static struct ocores_i2c_platform_data ocores_platform_data = {
85 	.num_devices = ARRAY_SIZE(tqmx86_i2c_devices),
86 	.devices = tqmx86_i2c_devices,
87 };
88 
89 static const struct mfd_cell tqmx86_i2c_soft_dev[] = {
90 	{
91 		.name = "ocores-i2c",
92 		.platform_data = &ocores_platform_data,
93 		.pdata_size = sizeof(ocores_platform_data),
94 		.resources = tqmx_i2c_soft_resources,
95 		.num_resources = ARRAY_SIZE(tqmx_i2c_soft_resources),
96 	},
97 };
98 
99 static const struct mfd_cell tqmx86_devs[] = {
100 	{
101 		.name = "tqmx86-wdt",
102 		.resources = tqmx_watchdog_resources,
103 		.num_resources = ARRAY_SIZE(tqmx_watchdog_resources),
104 		.ignore_resource_conflicts = true,
105 	},
106 	{
107 		.name = "tqmx86-gpio",
108 		.resources = tqmx_gpio_resources,
109 		.num_resources = ARRAY_SIZE(tqmx_gpio_resources),
110 		.ignore_resource_conflicts = true,
111 	},
112 };
113 
114 static const char *tqmx86_board_id_to_name(u8 board_id)
115 {
116 	switch (board_id) {
117 	case TQMX86_REG_BOARD_ID_E38M:
118 		return "TQMxE38M";
119 	case TQMX86_REG_BOARD_ID_50UC:
120 		return "TQMx50UC";
121 	case TQMX86_REG_BOARD_ID_E38C:
122 		return "TQMxE38C";
123 	case TQMX86_REG_BOARD_ID_60EB:
124 		return "TQMx60EB";
125 	case TQMX86_REG_BOARD_ID_E39M:
126 		return "TQMxE39M";
127 	case TQMX86_REG_BOARD_ID_E39C:
128 		return "TQMxE39C";
129 	case TQMX86_REG_BOARD_ID_E39x:
130 		return "TQMxE39x";
131 	case TQMX86_REG_BOARD_ID_70EB:
132 		return "TQMx70EB";
133 	case TQMX86_REG_BOARD_ID_80UC:
134 		return "TQMx80UC";
135 	case TQMX86_REG_BOARD_ID_110EB:
136 		return "TQMx110EB";
137 	case TQMX86_REG_BOARD_ID_E40M:
138 		return "TQMxE40M";
139 	case TQMX86_REG_BOARD_ID_E40S:
140 		return "TQMxE40S";
141 	case TQMX86_REG_BOARD_ID_E40C1:
142 		return "TQMxE40C1";
143 	case TQMX86_REG_BOARD_ID_E40C2:
144 		return "TQMxE40C2";
145 	default:
146 		return "Unknown";
147 	}
148 }
149 
150 static int tqmx86_board_id_to_clk_rate(struct device *dev, u8 board_id)
151 {
152 	switch (board_id) {
153 	case TQMX86_REG_BOARD_ID_50UC:
154 	case TQMX86_REG_BOARD_ID_60EB:
155 	case TQMX86_REG_BOARD_ID_70EB:
156 	case TQMX86_REG_BOARD_ID_80UC:
157 	case TQMX86_REG_BOARD_ID_110EB:
158 	case TQMX86_REG_BOARD_ID_E40M:
159 	case TQMX86_REG_BOARD_ID_E40S:
160 	case TQMX86_REG_BOARD_ID_E40C1:
161 	case TQMX86_REG_BOARD_ID_E40C2:
162 		return 24000;
163 	case TQMX86_REG_BOARD_ID_E39M:
164 	case TQMX86_REG_BOARD_ID_E39C:
165 	case TQMX86_REG_BOARD_ID_E39x:
166 		return 25000;
167 	case TQMX86_REG_BOARD_ID_E38M:
168 	case TQMX86_REG_BOARD_ID_E38C:
169 		return 33000;
170 	default:
171 		dev_warn(dev, "unknown board %d, assuming 24MHz LPC clock\n",
172 			 board_id);
173 		return 24000;
174 	}
175 }
176 
177 static int tqmx86_probe(struct platform_device *pdev)
178 {
179 	u8 board_id, rev, i2c_det, io_ext_int_val;
180 	struct device *dev = &pdev->dev;
181 	u8 gpio_irq_cfg, readback;
182 	const char *board_name;
183 	void __iomem *io_base;
184 	int err;
185 
186 	switch (gpio_irq) {
187 	case 0:
188 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_NONE;
189 		break;
190 	case 7:
191 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_7;
192 		break;
193 	case 9:
194 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_9;
195 		break;
196 	case 12:
197 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_12;
198 		break;
199 	default:
200 		pr_err("tqmx86: Invalid GPIO IRQ (%d)\n", gpio_irq);
201 		return -EINVAL;
202 	}
203 
204 	io_base = devm_ioport_map(dev, TQMX86_IOBASE, TQMX86_IOSIZE);
205 	if (!io_base)
206 		return -ENOMEM;
207 
208 	board_id = ioread8(io_base + TQMX86_REG_BOARD_ID);
209 	board_name = tqmx86_board_id_to_name(board_id);
210 	rev = ioread8(io_base + TQMX86_REG_BOARD_REV);
211 
212 	dev_info(dev,
213 		 "Found %s - Board ID %d, PCB Revision %d, PLD Revision %d\n",
214 		 board_name, board_id, rev >> 4, rev & 0xf);
215 
216 	i2c_det = ioread8(io_base + TQMX86_REG_I2C_DETECT);
217 
218 	if (gpio_irq_cfg) {
219 		io_ext_int_val =
220 			gpio_irq_cfg << TQMX86_REG_IO_EXT_INT_GPIO_SHIFT;
221 		iowrite8(io_ext_int_val, io_base + TQMX86_REG_IO_EXT_INT);
222 		readback = ioread8(io_base + TQMX86_REG_IO_EXT_INT);
223 		if (readback != io_ext_int_val) {
224 			dev_warn(dev, "GPIO interrupts not supported.\n");
225 			return -EINVAL;
226 		}
227 
228 		/* Assumes the IRQ resource is first. */
229 		tqmx_gpio_resources[0].start = gpio_irq;
230 	} else {
231 		tqmx_gpio_resources[0].flags = 0;
232 	}
233 
234 	ocores_platform_data.clock_khz = tqmx86_board_id_to_clk_rate(dev, board_id);
235 
236 	if (i2c_det == TQMX86_REG_I2C_DETECT_SOFT) {
237 		err = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
238 					   tqmx86_i2c_soft_dev,
239 					   ARRAY_SIZE(tqmx86_i2c_soft_dev),
240 					   NULL, 0, NULL);
241 		if (err)
242 			return err;
243 	}
244 
245 	return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
246 				    tqmx86_devs,
247 				    ARRAY_SIZE(tqmx86_devs),
248 				    NULL, 0, NULL);
249 }
250 
251 static int tqmx86_create_platform_device(const struct dmi_system_id *id)
252 {
253 	struct platform_device *pdev;
254 	int err;
255 
256 	pdev = platform_device_alloc("tqmx86", -1);
257 	if (!pdev)
258 		return -ENOMEM;
259 
260 	err = platform_device_add(pdev);
261 	if (err)
262 		platform_device_put(pdev);
263 
264 	return err;
265 }
266 
267 static const struct dmi_system_id tqmx86_dmi_table[] __initconst = {
268 	{
269 		.ident = "TQMX86",
270 		.matches = {
271 			DMI_MATCH(DMI_SYS_VENDOR, "TQ-Group"),
272 			DMI_MATCH(DMI_PRODUCT_NAME, "TQMx"),
273 		},
274 		.callback = tqmx86_create_platform_device,
275 	},
276 	{
277 		.ident = "TQMX86",
278 		.matches = {
279 			DMI_MATCH(DMI_SYS_VENDOR, "TQ-Systems"),
280 			DMI_MATCH(DMI_PRODUCT_NAME, "TQMx"),
281 		},
282 		.callback = tqmx86_create_platform_device,
283 	},
284 	{}
285 };
286 MODULE_DEVICE_TABLE(dmi, tqmx86_dmi_table);
287 
288 static struct platform_driver tqmx86_driver = {
289 	.driver		= {
290 		.name	= "tqmx86",
291 	},
292 	.probe		= tqmx86_probe,
293 };
294 
295 static int __init tqmx86_init(void)
296 {
297 	if (!dmi_check_system(tqmx86_dmi_table))
298 		return -ENODEV;
299 
300 	return platform_driver_register(&tqmx86_driver);
301 }
302 
303 module_init(tqmx86_init);
304 
305 MODULE_DESCRIPTION("TQMx86 PLD Core Driver");
306 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
307 MODULE_LICENSE("GPL");
308 MODULE_ALIAS("platform:tqmx86");
309