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13#include <linux/acpi.h>
14#include <linux/clk.h>
15#include <linux/clkdev.h>
16#include <linux/clk-provider.h>
17#include <linux/err.h>
18#include <linux/io.h>
19#include <linux/platform_device.h>
20#include <linux/platform_data/clk-lpss.h>
21#include <linux/pm_runtime.h>
22
23#include "internal.h"
24
25ACPI_MODULE_NAME("acpi_lpss");
26
27#define LPSS_CLK_SIZE 0x04
28#define LPSS_LTR_SIZE 0x18
29
30
31#define LPSS_GENERAL 0x08
32#define LPSS_GENERAL_LTR_MODE_SW BIT(2)
33#define LPSS_SW_LTR 0x10
34#define LPSS_AUTO_LTR 0x14
35#define LPSS_TX_INT 0x20
36#define LPSS_TX_INT_MASK BIT(1)
37
38struct lpss_shared_clock {
39 const char *name;
40 unsigned long rate;
41 struct clk *clk;
42};
43
44struct lpss_private_data;
45
46struct lpss_device_desc {
47 bool clk_required;
48 const char *clkdev_name;
49 bool ltr_required;
50 unsigned int prv_offset;
51 size_t prv_size_override;
52 bool clk_gate;
53 struct lpss_shared_clock *shared_clock;
54 void (*setup)(struct lpss_private_data *pdata);
55};
56
57static struct lpss_device_desc lpss_dma_desc = {
58 .clk_required = true,
59 .clkdev_name = "hclk",
60};
61
62struct lpss_private_data {
63 void __iomem *mmio_base;
64 resource_size_t mmio_size;
65 struct clk *clk;
66 const struct lpss_device_desc *dev_desc;
67};
68
69static void lpss_uart_setup(struct lpss_private_data *pdata)
70{
71 unsigned int tx_int_offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
72 u32 reg;
73
74 reg = readl(pdata->mmio_base + tx_int_offset);
75 writel(reg | LPSS_TX_INT_MASK, pdata->mmio_base + tx_int_offset);
76}
77
78static struct lpss_device_desc lpt_dev_desc = {
79 .clk_required = true,
80 .prv_offset = 0x800,
81 .ltr_required = true,
82 .clk_gate = true,
83};
84
85static struct lpss_device_desc lpt_uart_dev_desc = {
86 .clk_required = true,
87 .prv_offset = 0x800,
88 .ltr_required = true,
89 .clk_gate = true,
90 .setup = lpss_uart_setup,
91};
92
93static struct lpss_device_desc lpt_sdio_dev_desc = {
94 .prv_offset = 0x1000,
95 .prv_size_override = 0x1018,
96 .ltr_required = true,
97};
98
99static struct lpss_shared_clock uart_clock = {
100 .name = "uart_clk",
101 .rate = 44236800,
102};
103
104static struct lpss_device_desc byt_uart_dev_desc = {
105 .clk_required = true,
106 .prv_offset = 0x800,
107 .clk_gate = true,
108 .shared_clock = &uart_clock,
109 .setup = lpss_uart_setup,
110};
111
112static struct lpss_shared_clock spi_clock = {
113 .name = "spi_clk",
114 .rate = 50000000,
115};
116
117static struct lpss_device_desc byt_spi_dev_desc = {
118 .clk_required = true,
119 .prv_offset = 0x400,
120 .clk_gate = true,
121 .shared_clock = &spi_clock,
122};
123
124static struct lpss_device_desc byt_sdio_dev_desc = {
125 .clk_required = true,
126};
127
128static struct lpss_shared_clock i2c_clock = {
129 .name = "i2c_clk",
130 .rate = 100000000,
131};
132
133static struct lpss_device_desc byt_i2c_dev_desc = {
134 .clk_required = true,
135 .prv_offset = 0x800,
136 .shared_clock = &i2c_clock,
137};
138
139static const struct acpi_device_id acpi_lpss_device_ids[] = {
140
141 { "INTL9C60", (unsigned long)&lpss_dma_desc },
142
143
144 { "INT33C0", (unsigned long)&lpt_dev_desc },
145 { "INT33C1", (unsigned long)&lpt_dev_desc },
146 { "INT33C2", (unsigned long)&lpt_dev_desc },
147 { "INT33C3", (unsigned long)&lpt_dev_desc },
148 { "INT33C4", (unsigned long)&lpt_uart_dev_desc },
149 { "INT33C5", (unsigned long)&lpt_uart_dev_desc },
150 { "INT33C6", (unsigned long)&lpt_sdio_dev_desc },
151 { "INT33C7", },
152
153
154 { "80860F0A", (unsigned long)&byt_uart_dev_desc },
155 { "80860F0E", (unsigned long)&byt_spi_dev_desc },
156 { "80860F14", (unsigned long)&byt_sdio_dev_desc },
157 { "80860F41", (unsigned long)&byt_i2c_dev_desc },
158 { "INT33B2", },
159
160 { }
161};
162
163static int is_memory(struct acpi_resource *res, void *not_used)
164{
165 struct resource r;
166 return !acpi_dev_resource_memory(res, &r);
167}
168
169
170static struct platform_device *lpss_clk_dev;
171
172static inline void lpt_register_clock_device(void)
173{
174 lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
175}
176
177static int register_device_clock(struct acpi_device *adev,
178 struct lpss_private_data *pdata)
179{
180 const struct lpss_device_desc *dev_desc = pdata->dev_desc;
181 struct lpss_shared_clock *shared_clock = dev_desc->shared_clock;
182 struct clk *clk = ERR_PTR(-ENODEV);
183 struct lpss_clk_data *clk_data;
184 const char *parent;
185
186 if (!lpss_clk_dev)
187 lpt_register_clock_device();
188
189 clk_data = platform_get_drvdata(lpss_clk_dev);
190 if (!clk_data)
191 return -ENODEV;
192
193 if (dev_desc->clkdev_name) {
194 clk_register_clkdev(clk_data->clk, dev_desc->clkdev_name,
195 dev_name(&adev->dev));
196 return 0;
197 }
198
199 if (!pdata->mmio_base
200 || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
201 return -ENODATA;
202
203 parent = clk_data->name;
204
205 if (shared_clock) {
206 clk = shared_clock->clk;
207 if (!clk) {
208 clk = clk_register_fixed_rate(NULL, shared_clock->name,
209 "lpss_clk", 0,
210 shared_clock->rate);
211 shared_clock->clk = clk;
212 }
213 parent = shared_clock->name;
214 }
215
216 if (dev_desc->clk_gate) {
217 clk = clk_register_gate(NULL, dev_name(&adev->dev), parent, 0,
218 pdata->mmio_base + dev_desc->prv_offset,
219 0, 0, NULL);
220 pdata->clk = clk;
221 }
222
223 if (IS_ERR(clk))
224 return PTR_ERR(clk);
225
226 clk_register_clkdev(clk, NULL, dev_name(&adev->dev));
227 return 0;
228}
229
230static int acpi_lpss_create_device(struct acpi_device *adev,
231 const struct acpi_device_id *id)
232{
233 struct lpss_device_desc *dev_desc;
234 struct lpss_private_data *pdata;
235 struct resource_list_entry *rentry;
236 struct list_head resource_list;
237 int ret;
238
239 dev_desc = (struct lpss_device_desc *)id->driver_data;
240 if (!dev_desc)
241 return acpi_create_platform_device(adev, id);
242
243 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
244 if (!pdata)
245 return -ENOMEM;
246
247 INIT_LIST_HEAD(&resource_list);
248 ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
249 if (ret < 0)
250 goto err_out;
251
252 list_for_each_entry(rentry, &resource_list, node)
253 if (resource_type(&rentry->res) == IORESOURCE_MEM) {
254 if (dev_desc->prv_size_override)
255 pdata->mmio_size = dev_desc->prv_size_override;
256 else
257 pdata->mmio_size = resource_size(&rentry->res);
258 pdata->mmio_base = ioremap(rentry->res.start,
259 pdata->mmio_size);
260 pdata->dev_desc = dev_desc;
261 break;
262 }
263
264 acpi_dev_free_resource_list(&resource_list);
265
266 if (dev_desc->clk_required) {
267 ret = register_device_clock(adev, pdata);
268 if (ret) {
269
270 ret = 0;
271 goto err_out;
272 }
273 }
274
275
276
277
278
279
280 ret = acpi_device_fix_up_power(adev);
281 if (ret) {
282
283 ret = 0;
284 goto err_out;
285 }
286
287 if (dev_desc->setup)
288 dev_desc->setup(pdata);
289
290 adev->driver_data = pdata;
291 ret = acpi_create_platform_device(adev, id);
292 if (ret > 0)
293 return ret;
294
295 adev->driver_data = NULL;
296
297 err_out:
298 kfree(pdata);
299 return ret;
300}
301
302static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
303{
304 struct acpi_device *adev;
305 struct lpss_private_data *pdata;
306 unsigned long flags;
307 int ret;
308
309 ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
310 if (WARN_ON(ret))
311 return ret;
312
313 spin_lock_irqsave(&dev->power.lock, flags);
314 if (pm_runtime_suspended(dev)) {
315 ret = -EAGAIN;
316 goto out;
317 }
318 pdata = acpi_driver_data(adev);
319 if (WARN_ON(!pdata || !pdata->mmio_base)) {
320 ret = -ENODEV;
321 goto out;
322 }
323 *val = readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
324
325 out:
326 spin_unlock_irqrestore(&dev->power.lock, flags);
327 return ret;
328}
329
330static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
331 char *buf)
332{
333 u32 ltr_value = 0;
334 unsigned int reg;
335 int ret;
336
337 reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
338 ret = lpss_reg_read(dev, reg, <r_value);
339 if (ret)
340 return ret;
341
342 return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
343}
344
345static ssize_t lpss_ltr_mode_show(struct device *dev,
346 struct device_attribute *attr, char *buf)
347{
348 u32 ltr_mode = 0;
349 char *outstr;
350 int ret;
351
352 ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode);
353 if (ret)
354 return ret;
355
356 outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
357 return sprintf(buf, "%s\n", outstr);
358}
359
360static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
361static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
362static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
363
364static struct attribute *lpss_attrs[] = {
365 &dev_attr_auto_ltr.attr,
366 &dev_attr_sw_ltr.attr,
367 &dev_attr_ltr_mode.attr,
368 NULL,
369};
370
371static struct attribute_group lpss_attr_group = {
372 .attrs = lpss_attrs,
373 .name = "lpss_ltr",
374};
375
376static int acpi_lpss_platform_notify(struct notifier_block *nb,
377 unsigned long action, void *data)
378{
379 struct platform_device *pdev = to_platform_device(data);
380 struct lpss_private_data *pdata;
381 struct acpi_device *adev;
382 const struct acpi_device_id *id;
383 int ret = 0;
384
385 id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
386 if (!id || !id->driver_data)
387 return 0;
388
389 if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
390 return 0;
391
392 pdata = acpi_driver_data(adev);
393 if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required)
394 return 0;
395
396 if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
397 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
398 return 0;
399 }
400
401 if (action == BUS_NOTIFY_ADD_DEVICE)
402 ret = sysfs_create_group(&pdev->dev.kobj, &lpss_attr_group);
403 else if (action == BUS_NOTIFY_DEL_DEVICE)
404 sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
405
406 return ret;
407}
408
409static struct notifier_block acpi_lpss_nb = {
410 .notifier_call = acpi_lpss_platform_notify,
411};
412
413static struct acpi_scan_handler lpss_handler = {
414 .ids = acpi_lpss_device_ids,
415 .attach = acpi_lpss_create_device,
416};
417
418void __init acpi_lpss_init(void)
419{
420 if (!lpt_clk_init()) {
421 bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
422 acpi_scan_add_handler(&lpss_handler);
423 }
424}
425
