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1/*
2 * omap-rng.c - RNG driver for TI OMAP CPU family
3 *
4 * Author: Deepak Saxena <dsaxena@plexity.net>
5 *
6 * Copyright 2005 (c) MontaVista Software, Inc.
7 *
8 * Mostly based on original driver:
9 *
10 * Copyright (C) 2005 Nokia Corporation
11 * Author: Juha Yrjölä <juha.yrjola@nokia.com>
12 *
13 * This file is licensed under the terms of the GNU General Public
14 * License version 2. This program is licensed "as is" without any
15 * warranty of any kind, whether express or implied.
16 */
17
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/random.h>
21#include <linux/clk.h>
22#include <linux/err.h>
23#include <linux/platform_device.h>
24#include <linux/hw_random.h>
25#include <linux/delay.h>
26
27#include <asm/io.h>
28
29#define RNG_OUT_REG 0x00 /* Output register */
30#define RNG_STAT_REG 0x04 /* Status register
31 [0] = STAT_BUSY */
32#define RNG_ALARM_REG 0x24 /* Alarm register
33 [7:0] = ALARM_COUNTER */
34#define RNG_CONFIG_REG 0x28 /* Configuration register
35 [11:6] = RESET_COUNT
36 [5:3] = RING2_DELAY
37 [2:0] = RING1_DELAY */
38#define RNG_REV_REG 0x3c /* Revision register
39 [7:0] = REV_NB */
40#define RNG_MASK_REG 0x40 /* Mask and reset register
41 [2] = IT_EN
42 [1] = SOFTRESET
43 [0] = AUTOIDLE */
44#define RNG_SYSSTATUS 0x44 /* System status
45 [0] = RESETDONE */
46
47static void __iomem *rng_base;
48static struct clk *rng_ick;
49static struct platform_device *rng_dev;
50
51static inline u32 omap_rng_read_reg(int reg)
52{
53 return __raw_readl(rng_base + reg);
54}
55
56static inline void omap_rng_write_reg(int reg, u32 val)
57{
58 __raw_writel(val, rng_base + reg);
59}
60
61static int omap_rng_data_present(struct hwrng *rng, int wait)
62{
63 int data, i;
64
65 for (i = 0; i < 20; i++) {
66 data = omap_rng_read_reg(RNG_STAT_REG) ? 0 : 1;
67 if (data || !wait)
68 break;
69 /* RNG produces data fast enough (2+ MBit/sec, even
70 * during "rngtest" loads, that these delays don't
71 * seem to trigger. We *could* use the RNG IRQ, but
72 * that'd be higher overhead ... so why bother?
73 */
74 udelay(10);
75 }
76 return data;
77}
78
79static int omap_rng_data_read(struct hwrng *rng, u32 *data)
80{
81 *data = omap_rng_read_reg(RNG_OUT_REG);
82
83 return 4;
84}
85
86static struct hwrng omap_rng_ops = {
87 .name = "omap",
88 .data_present = omap_rng_data_present,
89 .data_read = omap_rng_data_read,
90};
91
92static int __devinit omap_rng_probe(struct platform_device *pdev)
93{
94 struct resource *res;
95 int ret;
96
97 /*
98 * A bit ugly, and it will never actually happen but there can
99 * be only one RNG and this catches any bork
100 */
101 if (rng_dev)
102 return -EBUSY;
103
104 if (cpu_is_omap24xx()) {
105 rng_ick = clk_get(&pdev->dev, "ick");
106 if (IS_ERR(rng_ick)) {
107 dev_err(&pdev->dev, "Could not get rng_ick\n");
108 ret = PTR_ERR(rng_ick);
109 return ret;
110 } else
111 clk_enable(rng_ick);
112 }
113
114 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
115
116 if (!res) {
117 ret = -ENOENT;
118 goto err_region;
119 }
120
121 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
122 ret = -EBUSY;
123 goto err_region;
124 }
125
126 dev_set_drvdata(&pdev->dev, res);
127 rng_base = ioremap(res->start, resource_size(res));
128 if (!rng_base) {
129 ret = -ENOMEM;
130 goto err_ioremap;
131 }
132
133 ret = hwrng_register(&omap_rng_ops);
134 if (ret)
135 goto err_register;
136
137 dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n",
138 omap_rng_read_reg(RNG_REV_REG));
139 omap_rng_write_reg(RNG_MASK_REG, 0x1);
140
141 rng_dev = pdev;
142
143 return 0;
144
145err_register:
146 iounmap(rng_base);
147 rng_base = NULL;
148err_ioremap:
149 release_mem_region(res->start, resource_size(res));
150err_region:
151 if (cpu_is_omap24xx()) {
152 clk_disable(rng_ick);
153 clk_put(rng_ick);
154 }
155 return ret;
156}
157
158static int __exit omap_rng_remove(struct platform_device *pdev)
159{
160 struct resource *res = dev_get_drvdata(&pdev->dev);
161
162 hwrng_unregister(&omap_rng_ops);
163
164 omap_rng_write_reg(RNG_MASK_REG, 0x0);
165
166 iounmap(rng_base);
167
168 if (cpu_is_omap24xx()) {
169 clk_disable(rng_ick);
170 clk_put(rng_ick);
171 }
172
173 release_mem_region(res->start, resource_size(res));
174 rng_base = NULL;
175
176 return 0;
177}
178
179#ifdef CONFIG_PM
180
181static int omap_rng_suspend(struct platform_device *pdev, pm_message_t message)
182{
183 omap_rng_write_reg(RNG_MASK_REG, 0x0);
184 return 0;
185}
186
187static int omap_rng_resume(struct platform_device *pdev)
188{
189 omap_rng_write_reg(RNG_MASK_REG, 0x1);
190 return 0;
191}
192
193#else
194
195#define omap_rng_suspend NULL
196#define omap_rng_resume NULL
197
198#endif
199
200/* work with hotplug and coldplug */
201MODULE_ALIAS("platform:omap_rng");
202
203static struct platform_driver omap_rng_driver = {
204 .driver = {
205 .name = "omap_rng",
206 .owner = THIS_MODULE,
207 },
208 .probe = omap_rng_probe,
209 .remove = __exit_p(omap_rng_remove),
210 .suspend = omap_rng_suspend,
211 .resume = omap_rng_resume
212};
213
214static int __init omap_rng_init(void)
215{
216 if (!cpu_is_omap16xx() && !cpu_is_omap24xx())
217 return -ENODEV;
218
219 return platform_driver_register(&omap_rng_driver);
220}
221
222static void __exit omap_rng_exit(void)
223{
224 platform_driver_unregister(&omap_rng_driver);
225}
226
227module_init(omap_rng_init);
228module_exit(omap_rng_exit);
229
230MODULE_AUTHOR("Deepak Saxena (and others)");
231MODULE_LICENSE("GPL");
1/*
2 * omap-rng.c - RNG driver for TI OMAP CPU family
3 *
4 * Author: Deepak Saxena <dsaxena@plexity.net>
5 *
6 * Copyright 2005 (c) MontaVista Software, Inc.
7 *
8 * Mostly based on original driver:
9 *
10 * Copyright (C) 2005 Nokia Corporation
11 * Author: Juha Yrjölä <juha.yrjola@nokia.com>
12 *
13 * This file is licensed under the terms of the GNU General Public
14 * License version 2. This program is licensed "as is" without any
15 * warranty of any kind, whether express or implied.
16 */
17
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/random.h>
21#include <linux/err.h>
22#include <linux/platform_device.h>
23#include <linux/hw_random.h>
24#include <linux/delay.h>
25#include <linux/slab.h>
26#include <linux/pm_runtime.h>
27#include <linux/of.h>
28#include <linux/of_device.h>
29#include <linux/of_address.h>
30#include <linux/interrupt.h>
31#include <linux/clk.h>
32
33#include <asm/io.h>
34
35#define RNG_REG_STATUS_RDY (1 << 0)
36
37#define RNG_REG_INTACK_RDY_MASK (1 << 0)
38#define RNG_REG_INTACK_SHUTDOWN_OFLO_MASK (1 << 1)
39#define RNG_SHUTDOWN_OFLO_MASK (1 << 1)
40
41#define RNG_CONTROL_STARTUP_CYCLES_SHIFT 16
42#define RNG_CONTROL_STARTUP_CYCLES_MASK (0xffff << 16)
43#define RNG_CONTROL_ENABLE_TRNG_SHIFT 10
44#define RNG_CONTROL_ENABLE_TRNG_MASK (1 << 10)
45
46#define RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT 16
47#define RNG_CONFIG_MAX_REFIL_CYCLES_MASK (0xffff << 16)
48#define RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT 0
49#define RNG_CONFIG_MIN_REFIL_CYCLES_MASK (0xff << 0)
50
51#define RNG_CONTROL_STARTUP_CYCLES 0xff
52#define RNG_CONFIG_MIN_REFIL_CYCLES 0x21
53#define RNG_CONFIG_MAX_REFIL_CYCLES 0x22
54
55#define RNG_ALARMCNT_ALARM_TH_SHIFT 0x0
56#define RNG_ALARMCNT_ALARM_TH_MASK (0xff << 0)
57#define RNG_ALARMCNT_SHUTDOWN_TH_SHIFT 16
58#define RNG_ALARMCNT_SHUTDOWN_TH_MASK (0x1f << 16)
59#define RNG_ALARM_THRESHOLD 0xff
60#define RNG_SHUTDOWN_THRESHOLD 0x4
61
62#define RNG_REG_FROENABLE_MASK 0xffffff
63#define RNG_REG_FRODETUNE_MASK 0xffffff
64
65#define OMAP2_RNG_OUTPUT_SIZE 0x4
66#define OMAP4_RNG_OUTPUT_SIZE 0x8
67#define EIP76_RNG_OUTPUT_SIZE 0x10
68
69enum {
70 RNG_OUTPUT_0_REG = 0,
71 RNG_OUTPUT_1_REG,
72 RNG_OUTPUT_2_REG,
73 RNG_OUTPUT_3_REG,
74 RNG_STATUS_REG,
75 RNG_INTMASK_REG,
76 RNG_INTACK_REG,
77 RNG_CONTROL_REG,
78 RNG_CONFIG_REG,
79 RNG_ALARMCNT_REG,
80 RNG_FROENABLE_REG,
81 RNG_FRODETUNE_REG,
82 RNG_ALARMMASK_REG,
83 RNG_ALARMSTOP_REG,
84 RNG_REV_REG,
85 RNG_SYSCONFIG_REG,
86};
87
88static const u16 reg_map_omap2[] = {
89 [RNG_OUTPUT_0_REG] = 0x0,
90 [RNG_STATUS_REG] = 0x4,
91 [RNG_CONFIG_REG] = 0x28,
92 [RNG_REV_REG] = 0x3c,
93 [RNG_SYSCONFIG_REG] = 0x40,
94};
95
96static const u16 reg_map_omap4[] = {
97 [RNG_OUTPUT_0_REG] = 0x0,
98 [RNG_OUTPUT_1_REG] = 0x4,
99 [RNG_STATUS_REG] = 0x8,
100 [RNG_INTMASK_REG] = 0xc,
101 [RNG_INTACK_REG] = 0x10,
102 [RNG_CONTROL_REG] = 0x14,
103 [RNG_CONFIG_REG] = 0x18,
104 [RNG_ALARMCNT_REG] = 0x1c,
105 [RNG_FROENABLE_REG] = 0x20,
106 [RNG_FRODETUNE_REG] = 0x24,
107 [RNG_ALARMMASK_REG] = 0x28,
108 [RNG_ALARMSTOP_REG] = 0x2c,
109 [RNG_REV_REG] = 0x1FE0,
110 [RNG_SYSCONFIG_REG] = 0x1FE4,
111};
112
113static const u16 reg_map_eip76[] = {
114 [RNG_OUTPUT_0_REG] = 0x0,
115 [RNG_OUTPUT_1_REG] = 0x4,
116 [RNG_OUTPUT_2_REG] = 0x8,
117 [RNG_OUTPUT_3_REG] = 0xc,
118 [RNG_STATUS_REG] = 0x10,
119 [RNG_INTACK_REG] = 0x10,
120 [RNG_CONTROL_REG] = 0x14,
121 [RNG_CONFIG_REG] = 0x18,
122 [RNG_ALARMCNT_REG] = 0x1c,
123 [RNG_FROENABLE_REG] = 0x20,
124 [RNG_FRODETUNE_REG] = 0x24,
125 [RNG_ALARMMASK_REG] = 0x28,
126 [RNG_ALARMSTOP_REG] = 0x2c,
127 [RNG_REV_REG] = 0x7c,
128};
129
130struct omap_rng_dev;
131/**
132 * struct omap_rng_pdata - RNG IP block-specific data
133 * @regs: Pointer to the register offsets structure.
134 * @data_size: No. of bytes in RNG output.
135 * @data_present: Callback to determine if data is available.
136 * @init: Callback for IP specific initialization sequence.
137 * @cleanup: Callback for IP specific cleanup sequence.
138 */
139struct omap_rng_pdata {
140 u16 *regs;
141 u32 data_size;
142 u32 (*data_present)(struct omap_rng_dev *priv);
143 int (*init)(struct omap_rng_dev *priv);
144 void (*cleanup)(struct omap_rng_dev *priv);
145};
146
147struct omap_rng_dev {
148 void __iomem *base;
149 struct device *dev;
150 const struct omap_rng_pdata *pdata;
151 struct hwrng rng;
152 struct clk *clk;
153};
154
155static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
156{
157 return __raw_readl(priv->base + priv->pdata->regs[reg]);
158}
159
160static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg,
161 u32 val)
162{
163 __raw_writel(val, priv->base + priv->pdata->regs[reg]);
164}
165
166
167static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
168 bool wait)
169{
170 struct omap_rng_dev *priv;
171 int i, present;
172
173 priv = (struct omap_rng_dev *)rng->priv;
174
175 if (max < priv->pdata->data_size)
176 return 0;
177
178 for (i = 0; i < 20; i++) {
179 present = priv->pdata->data_present(priv);
180 if (present || !wait)
181 break;
182
183 udelay(10);
184 }
185 if (!present)
186 return 0;
187
188 memcpy_fromio(data, priv->base + priv->pdata->regs[RNG_OUTPUT_0_REG],
189 priv->pdata->data_size);
190
191 if (priv->pdata->regs[RNG_INTACK_REG])
192 omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK);
193
194 return priv->pdata->data_size;
195}
196
197static int omap_rng_init(struct hwrng *rng)
198{
199 struct omap_rng_dev *priv;
200
201 priv = (struct omap_rng_dev *)rng->priv;
202 return priv->pdata->init(priv);
203}
204
205static void omap_rng_cleanup(struct hwrng *rng)
206{
207 struct omap_rng_dev *priv;
208
209 priv = (struct omap_rng_dev *)rng->priv;
210 priv->pdata->cleanup(priv);
211}
212
213
214static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv)
215{
216 return omap_rng_read(priv, RNG_STATUS_REG) ? 0 : 1;
217}
218
219static int omap2_rng_init(struct omap_rng_dev *priv)
220{
221 omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x1);
222 return 0;
223}
224
225static void omap2_rng_cleanup(struct omap_rng_dev *priv)
226{
227 omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x0);
228}
229
230static struct omap_rng_pdata omap2_rng_pdata = {
231 .regs = (u16 *)reg_map_omap2,
232 .data_size = OMAP2_RNG_OUTPUT_SIZE,
233 .data_present = omap2_rng_data_present,
234 .init = omap2_rng_init,
235 .cleanup = omap2_rng_cleanup,
236};
237
238#if defined(CONFIG_OF)
239static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv)
240{
241 return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY;
242}
243
244static int eip76_rng_init(struct omap_rng_dev *priv)
245{
246 u32 val;
247
248 /* Return if RNG is already running. */
249 if (omap_rng_read(priv, RNG_CONTROL_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
250 return 0;
251
252 /* Number of 512 bit blocks of raw Noise Source output data that must
253 * be processed by either the Conditioning Function or the
254 * SP 800-90 DRBG ‘BC_DF’ functionality to yield a ‘full entropy’
255 * output value.
256 */
257 val = 0x5 << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
258
259 /* Number of FRO samples that are XOR-ed together into one bit to be
260 * shifted into the main shift register
261 */
262 val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
263 omap_rng_write(priv, RNG_CONFIG_REG, val);
264
265 /* Enable all available FROs */
266 omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
267 omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
268
269 /* Enable TRNG */
270 val = RNG_CONTROL_ENABLE_TRNG_MASK;
271 omap_rng_write(priv, RNG_CONTROL_REG, val);
272
273 return 0;
274}
275
276static int omap4_rng_init(struct omap_rng_dev *priv)
277{
278 u32 val;
279
280 /* Return if RNG is already running. */
281 if (omap_rng_read(priv, RNG_CONTROL_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
282 return 0;
283
284 val = RNG_CONFIG_MIN_REFIL_CYCLES << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
285 val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
286 omap_rng_write(priv, RNG_CONFIG_REG, val);
287
288 omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
289 omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
290 val = RNG_ALARM_THRESHOLD << RNG_ALARMCNT_ALARM_TH_SHIFT;
291 val |= RNG_SHUTDOWN_THRESHOLD << RNG_ALARMCNT_SHUTDOWN_TH_SHIFT;
292 omap_rng_write(priv, RNG_ALARMCNT_REG, val);
293
294 val = RNG_CONTROL_STARTUP_CYCLES << RNG_CONTROL_STARTUP_CYCLES_SHIFT;
295 val |= RNG_CONTROL_ENABLE_TRNG_MASK;
296 omap_rng_write(priv, RNG_CONTROL_REG, val);
297
298 return 0;
299}
300
301static void omap4_rng_cleanup(struct omap_rng_dev *priv)
302{
303 int val;
304
305 val = omap_rng_read(priv, RNG_CONTROL_REG);
306 val &= ~RNG_CONTROL_ENABLE_TRNG_MASK;
307 omap_rng_write(priv, RNG_CONTROL_REG, val);
308}
309
310static irqreturn_t omap4_rng_irq(int irq, void *dev_id)
311{
312 struct omap_rng_dev *priv = dev_id;
313 u32 fro_detune, fro_enable;
314
315 /*
316 * Interrupt raised by a fro shutdown threshold, do the following:
317 * 1. Clear the alarm events.
318 * 2. De tune the FROs which are shutdown.
319 * 3. Re enable the shutdown FROs.
320 */
321 omap_rng_write(priv, RNG_ALARMMASK_REG, 0x0);
322 omap_rng_write(priv, RNG_ALARMSTOP_REG, 0x0);
323
324 fro_enable = omap_rng_read(priv, RNG_FROENABLE_REG);
325 fro_detune = ~fro_enable & RNG_REG_FRODETUNE_MASK;
326 fro_detune = fro_detune | omap_rng_read(priv, RNG_FRODETUNE_REG);
327 fro_enable = RNG_REG_FROENABLE_MASK;
328
329 omap_rng_write(priv, RNG_FRODETUNE_REG, fro_detune);
330 omap_rng_write(priv, RNG_FROENABLE_REG, fro_enable);
331
332 omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_SHUTDOWN_OFLO_MASK);
333
334 return IRQ_HANDLED;
335}
336
337static struct omap_rng_pdata omap4_rng_pdata = {
338 .regs = (u16 *)reg_map_omap4,
339 .data_size = OMAP4_RNG_OUTPUT_SIZE,
340 .data_present = omap4_rng_data_present,
341 .init = omap4_rng_init,
342 .cleanup = omap4_rng_cleanup,
343};
344
345static struct omap_rng_pdata eip76_rng_pdata = {
346 .regs = (u16 *)reg_map_eip76,
347 .data_size = EIP76_RNG_OUTPUT_SIZE,
348 .data_present = omap4_rng_data_present,
349 .init = eip76_rng_init,
350 .cleanup = omap4_rng_cleanup,
351};
352
353static const struct of_device_id omap_rng_of_match[] = {
354 {
355 .compatible = "ti,omap2-rng",
356 .data = &omap2_rng_pdata,
357 },
358 {
359 .compatible = "ti,omap4-rng",
360 .data = &omap4_rng_pdata,
361 },
362 {
363 .compatible = "inside-secure,safexcel-eip76",
364 .data = &eip76_rng_pdata,
365 },
366 {},
367};
368MODULE_DEVICE_TABLE(of, omap_rng_of_match);
369
370static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
371 struct platform_device *pdev)
372{
373 const struct of_device_id *match;
374 struct device *dev = &pdev->dev;
375 int irq, err;
376
377 match = of_match_device(of_match_ptr(omap_rng_of_match), dev);
378 if (!match) {
379 dev_err(dev, "no compatible OF match\n");
380 return -EINVAL;
381 }
382 priv->pdata = match->data;
383
384 if (of_device_is_compatible(dev->of_node, "ti,omap4-rng") ||
385 of_device_is_compatible(dev->of_node, "inside-secure,safexcel-eip76")) {
386 irq = platform_get_irq(pdev, 0);
387 if (irq < 0) {
388 dev_err(dev, "%s: error getting IRQ resource - %d\n",
389 __func__, irq);
390 return irq;
391 }
392
393 err = devm_request_irq(dev, irq, omap4_rng_irq,
394 IRQF_TRIGGER_NONE, dev_name(dev), priv);
395 if (err) {
396 dev_err(dev, "unable to request irq %d, err = %d\n",
397 irq, err);
398 return err;
399 }
400
401 priv->clk = devm_clk_get(&pdev->dev, NULL);
402 if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER)
403 return -EPROBE_DEFER;
404 if (!IS_ERR(priv->clk)) {
405 err = clk_prepare_enable(priv->clk);
406 if (err)
407 dev_err(&pdev->dev, "unable to enable the clk, "
408 "err = %d\n", err);
409 }
410
411 /*
412 * On OMAP4, enabling the shutdown_oflo interrupt is
413 * done in the interrupt mask register. There is no
414 * such register on EIP76, and it's enabled by the
415 * same bit in the control register
416 */
417 if (priv->pdata->regs[RNG_INTMASK_REG])
418 omap_rng_write(priv, RNG_INTMASK_REG,
419 RNG_SHUTDOWN_OFLO_MASK);
420 else
421 omap_rng_write(priv, RNG_CONTROL_REG,
422 RNG_SHUTDOWN_OFLO_MASK);
423 }
424 return 0;
425}
426#else
427static int of_get_omap_rng_device_details(struct omap_rng_dev *omap_rng,
428 struct platform_device *pdev)
429{
430 return -EINVAL;
431}
432#endif
433
434static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng)
435{
436 /* Only OMAP2/3 can be non-DT */
437 omap_rng->pdata = &omap2_rng_pdata;
438 return 0;
439}
440
441static int omap_rng_probe(struct platform_device *pdev)
442{
443 struct omap_rng_dev *priv;
444 struct resource *res;
445 struct device *dev = &pdev->dev;
446 int ret;
447
448 priv = devm_kzalloc(dev, sizeof(struct omap_rng_dev), GFP_KERNEL);
449 if (!priv)
450 return -ENOMEM;
451
452 priv->rng.read = omap_rng_do_read;
453 priv->rng.init = omap_rng_init;
454 priv->rng.cleanup = omap_rng_cleanup;
455
456 priv->rng.priv = (unsigned long)priv;
457 platform_set_drvdata(pdev, priv);
458 priv->dev = dev;
459
460 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
461 priv->base = devm_ioremap_resource(dev, res);
462 if (IS_ERR(priv->base)) {
463 ret = PTR_ERR(priv->base);
464 goto err_ioremap;
465 }
466
467 priv->rng.name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
468 if (!priv->rng.name) {
469 ret = -ENOMEM;
470 goto err_ioremap;
471 }
472
473 pm_runtime_enable(&pdev->dev);
474 ret = pm_runtime_get_sync(&pdev->dev);
475 if (ret < 0) {
476 dev_err(&pdev->dev, "Failed to runtime_get device: %d\n", ret);
477 pm_runtime_put_noidle(&pdev->dev);
478 goto err_ioremap;
479 }
480
481 ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) :
482 get_omap_rng_device_details(priv);
483 if (ret)
484 goto err_register;
485
486 ret = hwrng_register(&priv->rng);
487 if (ret)
488 goto err_register;
489
490 dev_info(&pdev->dev, "Random Number Generator ver. %02x\n",
491 omap_rng_read(priv, RNG_REV_REG));
492
493 return 0;
494
495err_register:
496 priv->base = NULL;
497 pm_runtime_put_sync(&pdev->dev);
498 pm_runtime_disable(&pdev->dev);
499
500 if (!IS_ERR(priv->clk))
501 clk_disable_unprepare(priv->clk);
502err_ioremap:
503 dev_err(dev, "initialization failed.\n");
504 return ret;
505}
506
507static int omap_rng_remove(struct platform_device *pdev)
508{
509 struct omap_rng_dev *priv = platform_get_drvdata(pdev);
510
511 hwrng_unregister(&priv->rng);
512
513 priv->pdata->cleanup(priv);
514
515 pm_runtime_put_sync(&pdev->dev);
516 pm_runtime_disable(&pdev->dev);
517
518 if (!IS_ERR(priv->clk))
519 clk_disable_unprepare(priv->clk);
520
521 return 0;
522}
523
524static int __maybe_unused omap_rng_suspend(struct device *dev)
525{
526 struct omap_rng_dev *priv = dev_get_drvdata(dev);
527
528 priv->pdata->cleanup(priv);
529 pm_runtime_put_sync(dev);
530
531 return 0;
532}
533
534static int __maybe_unused omap_rng_resume(struct device *dev)
535{
536 struct omap_rng_dev *priv = dev_get_drvdata(dev);
537 int ret;
538
539 ret = pm_runtime_get_sync(dev);
540 if (ret < 0) {
541 dev_err(dev, "Failed to runtime_get device: %d\n", ret);
542 pm_runtime_put_noidle(dev);
543 return ret;
544 }
545
546 priv->pdata->init(priv);
547
548 return 0;
549}
550
551static SIMPLE_DEV_PM_OPS(omap_rng_pm, omap_rng_suspend, omap_rng_resume);
552
553static struct platform_driver omap_rng_driver = {
554 .driver = {
555 .name = "omap_rng",
556 .pm = &omap_rng_pm,
557 .of_match_table = of_match_ptr(omap_rng_of_match),
558 },
559 .probe = omap_rng_probe,
560 .remove = omap_rng_remove,
561};
562
563module_platform_driver(omap_rng_driver);
564MODULE_ALIAS("platform:omap_rng");
565MODULE_AUTHOR("Deepak Saxena (and others)");
566MODULE_LICENSE("GPL");