treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / memory / atmel-ebi.c
blob14386d0b5f57800a9b68c2f2d10cd7df1d459488
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * EBI driver for Atmel chips
4 * inspired by the fsl weim bus driver
6 * Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
7 */
9 #include <linux/clk.h>
10 #include <linux/io.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/mfd/syscon/atmel-matrix.h>
13 #include <linux/mfd/syscon/atmel-smc.h>
14 #include <linux/init.h>
15 #include <linux/of_device.h>
16 #include <linux/regmap.h>
17 #include <soc/at91/atmel-sfr.h>
19 #define AT91_EBI_NUM_CS 8
21 struct atmel_ebi_dev_config {
22 int cs;
23 struct atmel_smc_cs_conf smcconf;
26 struct atmel_ebi;
28 struct atmel_ebi_dev {
29 struct list_head node;
30 struct atmel_ebi *ebi;
31 u32 mode;
32 int numcs;
33 struct atmel_ebi_dev_config configs[];
36 struct atmel_ebi_caps {
37 unsigned int available_cs;
38 unsigned int ebi_csa_offs;
39 const char *regmap_name;
40 void (*get_config)(struct atmel_ebi_dev *ebid,
41 struct atmel_ebi_dev_config *conf);
42 int (*xlate_config)(struct atmel_ebi_dev *ebid,
43 struct device_node *configs_np,
44 struct atmel_ebi_dev_config *conf);
45 void (*apply_config)(struct atmel_ebi_dev *ebid,
46 struct atmel_ebi_dev_config *conf);
49 struct atmel_ebi {
50 struct clk *clk;
51 struct regmap *regmap;
52 struct {
53 struct regmap *regmap;
54 struct clk *clk;
55 const struct atmel_hsmc_reg_layout *layout;
56 } smc;
58 struct device *dev;
59 const struct atmel_ebi_caps *caps;
60 struct list_head devs;
63 struct atmel_smc_timing_xlate {
64 const char *name;
65 int (*converter)(struct atmel_smc_cs_conf *conf,
66 unsigned int shift, unsigned int nycles);
67 unsigned int shift;
70 #define ATMEL_SMC_SETUP_XLATE(nm, pos) \
71 { .name = nm, .converter = atmel_smc_cs_conf_set_setup, .shift = pos}
73 #define ATMEL_SMC_PULSE_XLATE(nm, pos) \
74 { .name = nm, .converter = atmel_smc_cs_conf_set_pulse, .shift = pos}
76 #define ATMEL_SMC_CYCLE_XLATE(nm, pos) \
77 { .name = nm, .converter = atmel_smc_cs_conf_set_cycle, .shift = pos}
79 static void at91sam9_ebi_get_config(struct atmel_ebi_dev *ebid,
80 struct atmel_ebi_dev_config *conf)
82 atmel_smc_cs_conf_get(ebid->ebi->smc.regmap, conf->cs,
83 &conf->smcconf);
86 static void sama5_ebi_get_config(struct atmel_ebi_dev *ebid,
87 struct atmel_ebi_dev_config *conf)
89 atmel_hsmc_cs_conf_get(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
90 conf->cs, &conf->smcconf);
93 static const struct atmel_smc_timing_xlate timings_xlate_table[] = {
94 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-rd-setup-ns",
95 ATMEL_SMC_NCS_RD_SHIFT),
96 ATMEL_SMC_SETUP_XLATE("atmel,smc-ncs-wr-setup-ns",
97 ATMEL_SMC_NCS_WR_SHIFT),
98 ATMEL_SMC_SETUP_XLATE("atmel,smc-nrd-setup-ns", ATMEL_SMC_NRD_SHIFT),
99 ATMEL_SMC_SETUP_XLATE("atmel,smc-nwe-setup-ns", ATMEL_SMC_NWE_SHIFT),
100 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-rd-pulse-ns",
101 ATMEL_SMC_NCS_RD_SHIFT),
102 ATMEL_SMC_PULSE_XLATE("atmel,smc-ncs-wr-pulse-ns",
103 ATMEL_SMC_NCS_WR_SHIFT),
104 ATMEL_SMC_PULSE_XLATE("atmel,smc-nrd-pulse-ns", ATMEL_SMC_NRD_SHIFT),
105 ATMEL_SMC_PULSE_XLATE("atmel,smc-nwe-pulse-ns", ATMEL_SMC_NWE_SHIFT),
106 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nrd-cycle-ns", ATMEL_SMC_NRD_SHIFT),
107 ATMEL_SMC_CYCLE_XLATE("atmel,smc-nwe-cycle-ns", ATMEL_SMC_NWE_SHIFT),
110 static int atmel_ebi_xslate_smc_timings(struct atmel_ebi_dev *ebid,
111 struct device_node *np,
112 struct atmel_smc_cs_conf *smcconf)
114 unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
115 unsigned int clk_period_ns = NSEC_PER_SEC / clk_rate;
116 bool required = false;
117 unsigned int ncycles;
118 int ret, i;
119 u32 val;
121 ret = of_property_read_u32(np, "atmel,smc-tdf-ns", &val);
122 if (!ret) {
123 required = true;
124 ncycles = DIV_ROUND_UP(val, clk_period_ns);
125 if (ncycles > ATMEL_SMC_MODE_TDF_MAX) {
126 ret = -EINVAL;
127 goto out;
130 if (ncycles < ATMEL_SMC_MODE_TDF_MIN)
131 ncycles = ATMEL_SMC_MODE_TDF_MIN;
133 smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles);
136 for (i = 0; i < ARRAY_SIZE(timings_xlate_table); i++) {
137 const struct atmel_smc_timing_xlate *xlate;
139 xlate = &timings_xlate_table[i];
141 ret = of_property_read_u32(np, xlate->name, &val);
142 if (ret) {
143 if (!required)
144 continue;
145 else
146 break;
149 if (!required) {
150 ret = -EINVAL;
151 break;
154 ncycles = DIV_ROUND_UP(val, clk_period_ns);
155 ret = xlate->converter(smcconf, xlate->shift, ncycles);
156 if (ret)
157 goto out;
160 out:
161 if (ret) {
162 dev_err(ebid->ebi->dev,
163 "missing or invalid timings definition in %pOF",
164 np);
165 return ret;
168 return required;
171 static int atmel_ebi_xslate_smc_config(struct atmel_ebi_dev *ebid,
172 struct device_node *np,
173 struct atmel_ebi_dev_config *conf)
175 struct atmel_smc_cs_conf *smcconf = &conf->smcconf;
176 bool required = false;
177 const char *tmp_str;
178 u32 tmp;
179 int ret;
181 ret = of_property_read_u32(np, "atmel,smc-bus-width", &tmp);
182 if (!ret) {
183 switch (tmp) {
184 case 8:
185 smcconf->mode |= ATMEL_SMC_MODE_DBW_8;
186 break;
188 case 16:
189 smcconf->mode |= ATMEL_SMC_MODE_DBW_16;
190 break;
192 case 32:
193 smcconf->mode |= ATMEL_SMC_MODE_DBW_32;
194 break;
196 default:
197 return -EINVAL;
200 required = true;
203 if (of_property_read_bool(np, "atmel,smc-tdf-optimized")) {
204 smcconf->mode |= ATMEL_SMC_MODE_TDFMODE_OPTIMIZED;
205 required = true;
208 tmp_str = NULL;
209 of_property_read_string(np, "atmel,smc-byte-access-type", &tmp_str);
210 if (tmp_str && !strcmp(tmp_str, "write")) {
211 smcconf->mode |= ATMEL_SMC_MODE_BAT_WRITE;
212 required = true;
215 tmp_str = NULL;
216 of_property_read_string(np, "atmel,smc-read-mode", &tmp_str);
217 if (tmp_str && !strcmp(tmp_str, "nrd")) {
218 smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD;
219 required = true;
222 tmp_str = NULL;
223 of_property_read_string(np, "atmel,smc-write-mode", &tmp_str);
224 if (tmp_str && !strcmp(tmp_str, "nwe")) {
225 smcconf->mode |= ATMEL_SMC_MODE_WRITEMODE_NWE;
226 required = true;
229 tmp_str = NULL;
230 of_property_read_string(np, "atmel,smc-exnw-mode", &tmp_str);
231 if (tmp_str) {
232 if (!strcmp(tmp_str, "frozen"))
233 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_FROZEN;
234 else if (!strcmp(tmp_str, "ready"))
235 smcconf->mode |= ATMEL_SMC_MODE_EXNWMODE_READY;
236 else if (strcmp(tmp_str, "disabled"))
237 return -EINVAL;
239 required = true;
242 ret = of_property_read_u32(np, "atmel,smc-page-mode", &tmp);
243 if (!ret) {
244 switch (tmp) {
245 case 4:
246 smcconf->mode |= ATMEL_SMC_MODE_PS_4;
247 break;
249 case 8:
250 smcconf->mode |= ATMEL_SMC_MODE_PS_8;
251 break;
253 case 16:
254 smcconf->mode |= ATMEL_SMC_MODE_PS_16;
255 break;
257 case 32:
258 smcconf->mode |= ATMEL_SMC_MODE_PS_32;
259 break;
261 default:
262 return -EINVAL;
265 smcconf->mode |= ATMEL_SMC_MODE_PMEN;
266 required = true;
269 ret = atmel_ebi_xslate_smc_timings(ebid, np, &conf->smcconf);
270 if (ret < 0)
271 return -EINVAL;
273 if ((ret > 0 && !required) || (!ret && required)) {
274 dev_err(ebid->ebi->dev, "missing atmel,smc- properties in %pOF",
275 np);
276 return -EINVAL;
279 return required;
282 static void at91sam9_ebi_apply_config(struct atmel_ebi_dev *ebid,
283 struct atmel_ebi_dev_config *conf)
285 atmel_smc_cs_conf_apply(ebid->ebi->smc.regmap, conf->cs,
286 &conf->smcconf);
289 static void sama5_ebi_apply_config(struct atmel_ebi_dev *ebid,
290 struct atmel_ebi_dev_config *conf)
292 atmel_hsmc_cs_conf_apply(ebid->ebi->smc.regmap, ebid->ebi->smc.layout,
293 conf->cs, &conf->smcconf);
296 static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
297 int reg_cells)
299 const struct atmel_ebi_caps *caps = ebi->caps;
300 struct atmel_ebi_dev_config conf = { };
301 struct device *dev = ebi->dev;
302 struct atmel_ebi_dev *ebid;
303 unsigned long cslines = 0;
304 int ret, numcs = 0, nentries, i;
305 bool apply = false;
306 u32 cs;
308 nentries = of_property_count_elems_of_size(np, "reg",
309 reg_cells * sizeof(u32));
310 for (i = 0; i < nentries; i++) {
311 ret = of_property_read_u32_index(np, "reg", i * reg_cells,
312 &cs);
313 if (ret)
314 return ret;
316 if (cs >= AT91_EBI_NUM_CS ||
317 !(ebi->caps->available_cs & BIT(cs))) {
318 dev_err(dev, "invalid reg property in %pOF\n", np);
319 return -EINVAL;
322 if (!test_and_set_bit(cs, &cslines))
323 numcs++;
326 if (!numcs) {
327 dev_err(dev, "invalid reg property in %pOF\n", np);
328 return -EINVAL;
331 ebid = devm_kzalloc(ebi->dev, struct_size(ebid, configs, numcs),
332 GFP_KERNEL);
333 if (!ebid)
334 return -ENOMEM;
336 ebid->ebi = ebi;
337 ebid->numcs = numcs;
339 ret = caps->xlate_config(ebid, np, &conf);
340 if (ret < 0)
341 return ret;
342 else if (ret)
343 apply = true;
345 i = 0;
346 for_each_set_bit(cs, &cslines, AT91_EBI_NUM_CS) {
347 ebid->configs[i].cs = cs;
349 if (apply) {
350 conf.cs = cs;
351 caps->apply_config(ebid, &conf);
354 caps->get_config(ebid, &ebid->configs[i]);
357 * Attach the EBI device to the generic SMC logic if at least
358 * one "atmel,smc-" property is present.
360 if (ebi->caps->ebi_csa_offs && apply)
361 regmap_update_bits(ebi->regmap,
362 ebi->caps->ebi_csa_offs,
363 BIT(cs), 0);
365 i++;
368 list_add_tail(&ebid->node, &ebi->devs);
370 return 0;
373 static const struct atmel_ebi_caps at91sam9260_ebi_caps = {
374 .available_cs = 0xff,
375 .ebi_csa_offs = AT91SAM9260_MATRIX_EBICSA,
376 .regmap_name = "atmel,matrix",
377 .get_config = at91sam9_ebi_get_config,
378 .xlate_config = atmel_ebi_xslate_smc_config,
379 .apply_config = at91sam9_ebi_apply_config,
382 static const struct atmel_ebi_caps at91sam9261_ebi_caps = {
383 .available_cs = 0xff,
384 .ebi_csa_offs = AT91SAM9261_MATRIX_EBICSA,
385 .regmap_name = "atmel,matrix",
386 .get_config = at91sam9_ebi_get_config,
387 .xlate_config = atmel_ebi_xslate_smc_config,
388 .apply_config = at91sam9_ebi_apply_config,
391 static const struct atmel_ebi_caps at91sam9263_ebi0_caps = {
392 .available_cs = 0x3f,
393 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI0CSA,
394 .regmap_name = "atmel,matrix",
395 .get_config = at91sam9_ebi_get_config,
396 .xlate_config = atmel_ebi_xslate_smc_config,
397 .apply_config = at91sam9_ebi_apply_config,
400 static const struct atmel_ebi_caps at91sam9263_ebi1_caps = {
401 .available_cs = 0x7,
402 .ebi_csa_offs = AT91SAM9263_MATRIX_EBI1CSA,
403 .regmap_name = "atmel,matrix",
404 .get_config = at91sam9_ebi_get_config,
405 .xlate_config = atmel_ebi_xslate_smc_config,
406 .apply_config = at91sam9_ebi_apply_config,
409 static const struct atmel_ebi_caps at91sam9rl_ebi_caps = {
410 .available_cs = 0x3f,
411 .ebi_csa_offs = AT91SAM9RL_MATRIX_EBICSA,
412 .regmap_name = "atmel,matrix",
413 .get_config = at91sam9_ebi_get_config,
414 .xlate_config = atmel_ebi_xslate_smc_config,
415 .apply_config = at91sam9_ebi_apply_config,
418 static const struct atmel_ebi_caps at91sam9g45_ebi_caps = {
419 .available_cs = 0x3f,
420 .ebi_csa_offs = AT91SAM9G45_MATRIX_EBICSA,
421 .regmap_name = "atmel,matrix",
422 .get_config = at91sam9_ebi_get_config,
423 .xlate_config = atmel_ebi_xslate_smc_config,
424 .apply_config = at91sam9_ebi_apply_config,
427 static const struct atmel_ebi_caps at91sam9x5_ebi_caps = {
428 .available_cs = 0x3f,
429 .ebi_csa_offs = AT91SAM9X5_MATRIX_EBICSA,
430 .regmap_name = "atmel,matrix",
431 .get_config = at91sam9_ebi_get_config,
432 .xlate_config = atmel_ebi_xslate_smc_config,
433 .apply_config = at91sam9_ebi_apply_config,
436 static const struct atmel_ebi_caps sama5d3_ebi_caps = {
437 .available_cs = 0xf,
438 .get_config = sama5_ebi_get_config,
439 .xlate_config = atmel_ebi_xslate_smc_config,
440 .apply_config = sama5_ebi_apply_config,
443 static const struct atmel_ebi_caps sam9x60_ebi_caps = {
444 .available_cs = 0x3f,
445 .ebi_csa_offs = AT91_SFR_CCFG_EBICSA,
446 .regmap_name = "microchip,sfr",
447 .get_config = at91sam9_ebi_get_config,
448 .xlate_config = atmel_ebi_xslate_smc_config,
449 .apply_config = at91sam9_ebi_apply_config,
452 static const struct of_device_id atmel_ebi_id_table[] = {
454 .compatible = "atmel,at91sam9260-ebi",
455 .data = &at91sam9260_ebi_caps,
458 .compatible = "atmel,at91sam9261-ebi",
459 .data = &at91sam9261_ebi_caps,
462 .compatible = "atmel,at91sam9263-ebi0",
463 .data = &at91sam9263_ebi0_caps,
466 .compatible = "atmel,at91sam9263-ebi1",
467 .data = &at91sam9263_ebi1_caps,
470 .compatible = "atmel,at91sam9rl-ebi",
471 .data = &at91sam9rl_ebi_caps,
474 .compatible = "atmel,at91sam9g45-ebi",
475 .data = &at91sam9g45_ebi_caps,
478 .compatible = "atmel,at91sam9x5-ebi",
479 .data = &at91sam9x5_ebi_caps,
482 .compatible = "atmel,sama5d3-ebi",
483 .data = &sama5d3_ebi_caps,
486 .compatible = "microchip,sam9x60-ebi",
487 .data = &sam9x60_ebi_caps,
489 { /* sentinel */ }
492 static int atmel_ebi_dev_disable(struct atmel_ebi *ebi, struct device_node *np)
494 struct device *dev = ebi->dev;
495 struct property *newprop;
497 newprop = devm_kzalloc(dev, sizeof(*newprop), GFP_KERNEL);
498 if (!newprop)
499 return -ENOMEM;
501 newprop->name = devm_kstrdup(dev, "status", GFP_KERNEL);
502 if (!newprop->name)
503 return -ENOMEM;
505 newprop->value = devm_kstrdup(dev, "disabled", GFP_KERNEL);
506 if (!newprop->value)
507 return -ENOMEM;
509 newprop->length = sizeof("disabled");
511 return of_update_property(np, newprop);
514 static int atmel_ebi_probe(struct platform_device *pdev)
516 struct device *dev = &pdev->dev;
517 struct device_node *child, *np = dev->of_node, *smc_np;
518 const struct of_device_id *match;
519 struct atmel_ebi *ebi;
520 int ret, reg_cells;
521 struct clk *clk;
522 u32 val;
524 match = of_match_device(atmel_ebi_id_table, dev);
525 if (!match || !match->data)
526 return -EINVAL;
528 ebi = devm_kzalloc(dev, sizeof(*ebi), GFP_KERNEL);
529 if (!ebi)
530 return -ENOMEM;
532 platform_set_drvdata(pdev, ebi);
534 INIT_LIST_HEAD(&ebi->devs);
535 ebi->caps = match->data;
536 ebi->dev = dev;
538 clk = devm_clk_get(dev, NULL);
539 if (IS_ERR(clk))
540 return PTR_ERR(clk);
542 ebi->clk = clk;
544 smc_np = of_parse_phandle(dev->of_node, "atmel,smc", 0);
546 ebi->smc.regmap = syscon_node_to_regmap(smc_np);
547 if (IS_ERR(ebi->smc.regmap))
548 return PTR_ERR(ebi->smc.regmap);
550 ebi->smc.layout = atmel_hsmc_get_reg_layout(smc_np);
551 if (IS_ERR(ebi->smc.layout))
552 return PTR_ERR(ebi->smc.layout);
554 ebi->smc.clk = of_clk_get(smc_np, 0);
555 if (IS_ERR(ebi->smc.clk)) {
556 if (PTR_ERR(ebi->smc.clk) != -ENOENT)
557 return PTR_ERR(ebi->smc.clk);
559 ebi->smc.clk = NULL;
561 ret = clk_prepare_enable(ebi->smc.clk);
562 if (ret)
563 return ret;
566 * The sama5d3 does not provide an EBICSA register and thus does need
567 * to access it.
569 if (ebi->caps->ebi_csa_offs) {
570 ebi->regmap =
571 syscon_regmap_lookup_by_phandle(np,
572 ebi->caps->regmap_name);
573 if (IS_ERR(ebi->regmap))
574 return PTR_ERR(ebi->regmap);
577 ret = of_property_read_u32(np, "#address-cells", &val);
578 if (ret) {
579 dev_err(dev, "missing #address-cells property\n");
580 return ret;
583 reg_cells = val;
585 ret = of_property_read_u32(np, "#size-cells", &val);
586 if (ret) {
587 dev_err(dev, "missing #address-cells property\n");
588 return ret;
591 reg_cells += val;
593 for_each_available_child_of_node(np, child) {
594 if (!of_find_property(child, "reg", NULL))
595 continue;
597 ret = atmel_ebi_dev_setup(ebi, child, reg_cells);
598 if (ret) {
599 dev_err(dev, "failed to configure EBI bus for %pOF, disabling the device",
600 child);
602 ret = atmel_ebi_dev_disable(ebi, child);
603 if (ret)
604 return ret;
608 return of_platform_populate(np, NULL, NULL, dev);
611 static __maybe_unused int atmel_ebi_resume(struct device *dev)
613 struct atmel_ebi *ebi = dev_get_drvdata(dev);
614 struct atmel_ebi_dev *ebid;
616 list_for_each_entry(ebid, &ebi->devs, node) {
617 int i;
619 for (i = 0; i < ebid->numcs; i++)
620 ebid->ebi->caps->apply_config(ebid, &ebid->configs[i]);
623 return 0;
626 static SIMPLE_DEV_PM_OPS(atmel_ebi_pm_ops, NULL, atmel_ebi_resume);
628 static struct platform_driver atmel_ebi_driver = {
629 .driver = {
630 .name = "atmel-ebi",
631 .of_match_table = atmel_ebi_id_table,
632 .pm = &atmel_ebi_pm_ops,
635 builtin_platform_driver_probe(atmel_ebi_driver, atmel_ebi_probe);