xref: /linux/arch/x86/platform/ts5500/ts5500.c (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Technologic Systems TS-5500 Single Board Computer support
4  *
5  * Copyright (C) 2013-2014 Savoir-faire Linux Inc.
6  *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
7  *
8  * This driver registers the Technologic Systems TS-5500 Single Board Computer
9  * (SBC) and its devices, and exposes information to userspace such as jumpers'
10  * state or available options. For further information about sysfs entries, see
11  * Documentation/ABI/testing/sysfs-platform-ts5500.
12  *
13  * This code may be extended to support similar x86-based platforms.
14  * Actually, the TS-5500 and TS-5400 are supported.
15  */
16 
17 #include <linux/delay.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/leds.h>
21 #include <linux/init.h>
22 #include <linux/platform_data/max197.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 
26 /* Product code register */
27 #define TS5500_PRODUCT_CODE_ADDR	0x74
28 #define TS5500_PRODUCT_CODE		0x60	/* TS-5500 product code */
29 #define TS5400_PRODUCT_CODE		0x40	/* TS-5400 product code */
30 
31 /* SRAM/RS-485/ADC options, and RS-485 RTS/Automatic RS-485 flags register */
32 #define TS5500_SRAM_RS485_ADC_ADDR	0x75
33 #define TS5500_SRAM			BIT(0)	/* SRAM option */
34 #define TS5500_RS485			BIT(1)	/* RS-485 option */
35 #define TS5500_ADC			BIT(2)	/* A/D converter option */
36 #define TS5500_RS485_RTS		BIT(6)	/* RTS for RS-485 */
37 #define TS5500_RS485_AUTO		BIT(7)	/* Automatic RS-485 */
38 
39 /* External Reset/Industrial Temperature Range options register */
40 #define TS5500_ERESET_ITR_ADDR		0x76
41 #define TS5500_ERESET			BIT(0)	/* External Reset option */
42 #define TS5500_ITR			BIT(1)	/* Indust. Temp. Range option */
43 
44 /* LED/Jumpers register */
45 #define TS5500_LED_JP_ADDR		0x77
46 #define TS5500_LED			BIT(0)	/* LED flag */
47 #define TS5500_JP1			BIT(1)	/* Automatic CMOS */
48 #define TS5500_JP2			BIT(2)	/* Enable Serial Console */
49 #define TS5500_JP3			BIT(3)	/* Write Enable Drive A */
50 #define TS5500_JP4			BIT(4)	/* Fast Console (115K baud) */
51 #define TS5500_JP5			BIT(5)	/* User Jumper */
52 #define TS5500_JP6			BIT(6)	/* Console on COM1 (req. JP2) */
53 #define TS5500_JP7			BIT(7)	/* Undocumented (Unused) */
54 
55 /* A/D Converter registers */
56 #define TS5500_ADC_CONV_BUSY_ADDR	0x195	/* Conversion state register */
57 #define TS5500_ADC_CONV_BUSY		BIT(0)
58 #define TS5500_ADC_CONV_INIT_LSB_ADDR	0x196	/* Start conv. / LSB register */
59 #define TS5500_ADC_CONV_MSB_ADDR	0x197	/* MSB register */
60 #define TS5500_ADC_CONV_DELAY		12	/* usec */
61 
62 /**
63  * struct ts5500_sbc - TS-5500 board description
64  * @name:	Board model name.
65  * @id:		Board product ID.
66  * @sram:	Flag for SRAM option.
67  * @rs485:	Flag for RS-485 option.
68  * @adc:	Flag for Analog/Digital converter option.
69  * @ereset:	Flag for External Reset option.
70  * @itr:	Flag for Industrial Temperature Range option.
71  * @jumpers:	Bitfield for jumpers' state.
72  */
73 struct ts5500_sbc {
74 	const char *name;
75 	int	id;
76 	bool	sram;
77 	bool	rs485;
78 	bool	adc;
79 	bool	ereset;
80 	bool	itr;
81 	u8	jumpers;
82 };
83 
84 /* Board signatures in BIOS shadow RAM */
85 static const struct {
86 	const char * const string;
87 	const ssize_t offset;
88 } ts5500_signatures[] __initconst = {
89 	{ "TS-5x00 AMD Elan", 0xb14 },
90 };
91 
ts5500_check_signature(void)92 static int __init ts5500_check_signature(void)
93 {
94 	void __iomem *bios;
95 	int i, ret = -ENODEV;
96 
97 	bios = ioremap(0xf0000, 0x10000);
98 	if (!bios)
99 		return -ENOMEM;
100 
101 	for (i = 0; i < ARRAY_SIZE(ts5500_signatures); i++) {
102 		if (check_signature(bios + ts5500_signatures[i].offset,
103 				    ts5500_signatures[i].string,
104 				    strlen(ts5500_signatures[i].string))) {
105 			ret = 0;
106 			break;
107 		}
108 	}
109 
110 	iounmap(bios);
111 	return ret;
112 }
113 
ts5500_detect_config(struct ts5500_sbc * sbc)114 static int __init ts5500_detect_config(struct ts5500_sbc *sbc)
115 {
116 	u8 tmp;
117 	int ret = 0;
118 
119 	if (!request_region(TS5500_PRODUCT_CODE_ADDR, 4, "ts5500"))
120 		return -EBUSY;
121 
122 	sbc->id = inb(TS5500_PRODUCT_CODE_ADDR);
123 	if (sbc->id == TS5500_PRODUCT_CODE) {
124 		sbc->name = "TS-5500";
125 	} else if (sbc->id == TS5400_PRODUCT_CODE) {
126 		sbc->name = "TS-5400";
127 	} else {
128 		pr_err("ts5500: unknown product code 0x%x\n", sbc->id);
129 		ret = -ENODEV;
130 		goto cleanup;
131 	}
132 
133 	tmp = inb(TS5500_SRAM_RS485_ADC_ADDR);
134 	sbc->sram = tmp & TS5500_SRAM;
135 	sbc->rs485 = tmp & TS5500_RS485;
136 	sbc->adc = tmp & TS5500_ADC;
137 
138 	tmp = inb(TS5500_ERESET_ITR_ADDR);
139 	sbc->ereset = tmp & TS5500_ERESET;
140 	sbc->itr = tmp & TS5500_ITR;
141 
142 	tmp = inb(TS5500_LED_JP_ADDR);
143 	sbc->jumpers = tmp & ~TS5500_LED;
144 
145 cleanup:
146 	release_region(TS5500_PRODUCT_CODE_ADDR, 4);
147 	return ret;
148 }
149 
name_show(struct device * dev,struct device_attribute * attr,char * buf)150 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
151 		char *buf)
152 {
153 	struct ts5500_sbc *sbc = dev_get_drvdata(dev);
154 
155 	return sprintf(buf, "%s\n", sbc->name);
156 }
157 static DEVICE_ATTR_RO(name);
158 
id_show(struct device * dev,struct device_attribute * attr,char * buf)159 static ssize_t id_show(struct device *dev, struct device_attribute *attr,
160 		char *buf)
161 {
162 	struct ts5500_sbc *sbc = dev_get_drvdata(dev);
163 
164 	return sprintf(buf, "0x%.2x\n", sbc->id);
165 }
166 static DEVICE_ATTR_RO(id);
167 
jumpers_show(struct device * dev,struct device_attribute * attr,char * buf)168 static ssize_t jumpers_show(struct device *dev, struct device_attribute *attr,
169 		char *buf)
170 {
171 	struct ts5500_sbc *sbc = dev_get_drvdata(dev);
172 
173 	return sprintf(buf, "0x%.2x\n", sbc->jumpers >> 1);
174 }
175 static DEVICE_ATTR_RO(jumpers);
176 
177 #define TS5500_ATTR_BOOL(_field)					\
178 	static ssize_t _field##_show(struct device *dev,		\
179 			struct device_attribute *attr, char *buf)	\
180 	{								\
181 		struct ts5500_sbc *sbc = dev_get_drvdata(dev);		\
182 									\
183 		return sprintf(buf, "%d\n", sbc->_field);		\
184 	}								\
185 	static DEVICE_ATTR_RO(_field)
186 
187 TS5500_ATTR_BOOL(sram);
188 TS5500_ATTR_BOOL(rs485);
189 TS5500_ATTR_BOOL(adc);
190 TS5500_ATTR_BOOL(ereset);
191 TS5500_ATTR_BOOL(itr);
192 
193 static struct attribute *ts5500_attributes[] = {
194 	&dev_attr_id.attr,
195 	&dev_attr_name.attr,
196 	&dev_attr_jumpers.attr,
197 	&dev_attr_sram.attr,
198 	&dev_attr_rs485.attr,
199 	&dev_attr_adc.attr,
200 	&dev_attr_ereset.attr,
201 	&dev_attr_itr.attr,
202 	NULL
203 };
204 
205 static const struct attribute_group ts5500_attr_group = {
206 	.attrs = ts5500_attributes,
207 };
208 
209 static struct resource ts5500_dio1_resource[] = {
210 	DEFINE_RES_IRQ_NAMED(7, "DIO1 interrupt"),
211 };
212 
213 static struct platform_device ts5500_dio1_pdev = {
214 	.name = "ts5500-dio1",
215 	.id = -1,
216 	.resource = ts5500_dio1_resource,
217 	.num_resources = 1,
218 };
219 
220 static struct resource ts5500_dio2_resource[] = {
221 	DEFINE_RES_IRQ_NAMED(6, "DIO2 interrupt"),
222 };
223 
224 static struct platform_device ts5500_dio2_pdev = {
225 	.name = "ts5500-dio2",
226 	.id = -1,
227 	.resource = ts5500_dio2_resource,
228 	.num_resources = 1,
229 };
230 
ts5500_led_set(struct led_classdev * led_cdev,enum led_brightness brightness)231 static void ts5500_led_set(struct led_classdev *led_cdev,
232 			   enum led_brightness brightness)
233 {
234 	outb(!!brightness, TS5500_LED_JP_ADDR);
235 }
236 
ts5500_led_get(struct led_classdev * led_cdev)237 static enum led_brightness ts5500_led_get(struct led_classdev *led_cdev)
238 {
239 	return (inb(TS5500_LED_JP_ADDR) & TS5500_LED) ? LED_FULL : LED_OFF;
240 }
241 
242 static struct led_classdev ts5500_led_cdev = {
243 	.name = "ts5500:green:",
244 	.brightness_set = ts5500_led_set,
245 	.brightness_get = ts5500_led_get,
246 };
247 
ts5500_adc_convert(u8 ctrl)248 static int ts5500_adc_convert(u8 ctrl)
249 {
250 	u8 lsb, msb;
251 
252 	/* Start conversion (ensure the 3 MSB are set to 0) */
253 	outb(ctrl & 0x1f, TS5500_ADC_CONV_INIT_LSB_ADDR);
254 
255 	/*
256 	 * The platform has CPLD logic driving the A/D converter.
257 	 * The conversion must complete within 11 microseconds,
258 	 * otherwise we have to re-initiate a conversion.
259 	 */
260 	udelay(TS5500_ADC_CONV_DELAY);
261 	if (inb(TS5500_ADC_CONV_BUSY_ADDR) & TS5500_ADC_CONV_BUSY)
262 		return -EBUSY;
263 
264 	/* Read the raw data */
265 	lsb = inb(TS5500_ADC_CONV_INIT_LSB_ADDR);
266 	msb = inb(TS5500_ADC_CONV_MSB_ADDR);
267 
268 	return (msb << 8) | lsb;
269 }
270 
271 static struct max197_platform_data ts5500_adc_pdata = {
272 	.convert = ts5500_adc_convert,
273 };
274 
275 static struct platform_device ts5500_adc_pdev = {
276 	.name = "max197",
277 	.id = -1,
278 	.dev = {
279 		.platform_data = &ts5500_adc_pdata,
280 	},
281 };
282 
ts5500_init(void)283 static int __init ts5500_init(void)
284 {
285 	struct platform_device *pdev;
286 	struct ts5500_sbc *sbc;
287 	int err;
288 
289 	/*
290 	 * There is no DMI available or PCI bridge subvendor info,
291 	 * only the BIOS provides a 16-bit identification call.
292 	 * It is safer to find a signature in the BIOS shadow RAM.
293 	 */
294 	err = ts5500_check_signature();
295 	if (err)
296 		return err;
297 
298 	pdev = platform_device_register_simple("ts5500", -1, NULL, 0);
299 	if (IS_ERR(pdev))
300 		return PTR_ERR(pdev);
301 
302 	sbc = devm_kzalloc(&pdev->dev, sizeof(struct ts5500_sbc), GFP_KERNEL);
303 	if (!sbc) {
304 		err = -ENOMEM;
305 		goto error;
306 	}
307 
308 	err = ts5500_detect_config(sbc);
309 	if (err)
310 		goto error;
311 
312 	platform_set_drvdata(pdev, sbc);
313 
314 	err = sysfs_create_group(&pdev->dev.kobj, &ts5500_attr_group);
315 	if (err)
316 		goto error;
317 
318 	if (sbc->id == TS5500_PRODUCT_CODE) {
319 		ts5500_dio1_pdev.dev.parent = &pdev->dev;
320 		if (platform_device_register(&ts5500_dio1_pdev))
321 			dev_warn(&pdev->dev, "DIO1 block registration failed\n");
322 		ts5500_dio2_pdev.dev.parent = &pdev->dev;
323 		if (platform_device_register(&ts5500_dio2_pdev))
324 			dev_warn(&pdev->dev, "DIO2 block registration failed\n");
325 	}
326 
327 	if (led_classdev_register(&pdev->dev, &ts5500_led_cdev))
328 		dev_warn(&pdev->dev, "LED registration failed\n");
329 
330 	if (sbc->adc) {
331 		ts5500_adc_pdev.dev.parent = &pdev->dev;
332 		if (platform_device_register(&ts5500_adc_pdev))
333 			dev_warn(&pdev->dev, "ADC registration failed\n");
334 	}
335 
336 	return 0;
337 error:
338 	platform_device_unregister(pdev);
339 	return err;
340 }
341 device_initcall(ts5500_init);
342