1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Altera Arria10 DevKit System Resource MFD Driver
  4 *
  5 * Author: Thor Thayer <tthayer@opensource.altera.com>
  6 *
  7 * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
  8 *
  9 * SPI access for Altera Arria10 MAX5 System Resource Chip
 10 *
 11 * Adapted from DA9052
 12 */
 13
 14#include <linux/mfd/altera-a10sr.h>
 15#include <linux/mfd/core.h>
 16#include <linux/init.h>
 17#include <linux/module.h>
 18#include <linux/of.h>
 19#include <linux/spi/spi.h>
 20
 21static const struct mfd_cell altr_a10sr_subdev_info[] = {
 22	{
 23		.name = "altr_a10sr_gpio",
 24		.of_compatible = "altr,a10sr-gpio",
 25	},
 26	{
 27		.name = "altr_a10sr_reset",
 28		.of_compatible = "altr,a10sr-reset",
 29	},
 30};
 31
 32static bool altr_a10sr_reg_readable(struct device *dev, unsigned int reg)
 33{
 34	switch (reg) {
 35	case ALTR_A10SR_VERSION_READ:
 36	case ALTR_A10SR_LED_REG:
 37	case ALTR_A10SR_PBDSW_REG:
 38	case ALTR_A10SR_PBDSW_IRQ_REG:
 39	case ALTR_A10SR_PWR_GOOD1_REG:
 40	case ALTR_A10SR_PWR_GOOD2_REG:
 41	case ALTR_A10SR_PWR_GOOD3_REG:
 42	case ALTR_A10SR_FMCAB_REG:
 43	case ALTR_A10SR_HPS_RST_REG:
 44	case ALTR_A10SR_USB_QSPI_REG:
 45	case ALTR_A10SR_SFPA_REG:
 46	case ALTR_A10SR_SFPB_REG:
 47	case ALTR_A10SR_I2C_M_REG:
 48	case ALTR_A10SR_WARM_RST_REG:
 49	case ALTR_A10SR_WR_KEY_REG:
 50	case ALTR_A10SR_PMBUS_REG:
 51		return true;
 52	default:
 53		return false;
 54	}
 55}
 56
 57static bool altr_a10sr_reg_writeable(struct device *dev, unsigned int reg)
 58{
 59	switch (reg) {
 60	case ALTR_A10SR_LED_REG:
 61	case ALTR_A10SR_PBDSW_IRQ_REG:
 62	case ALTR_A10SR_FMCAB_REG:
 63	case ALTR_A10SR_HPS_RST_REG:
 64	case ALTR_A10SR_USB_QSPI_REG:
 65	case ALTR_A10SR_SFPA_REG:
 66	case ALTR_A10SR_SFPB_REG:
 67	case ALTR_A10SR_WARM_RST_REG:
 68	case ALTR_A10SR_WR_KEY_REG:
 69	case ALTR_A10SR_PMBUS_REG:
 70		return true;
 71	default:
 72		return false;
 73	}
 74}
 75
 76static bool altr_a10sr_reg_volatile(struct device *dev, unsigned int reg)
 77{
 78	switch (reg) {
 79	case ALTR_A10SR_PBDSW_REG:
 80	case ALTR_A10SR_PBDSW_IRQ_REG:
 81	case ALTR_A10SR_PWR_GOOD1_REG:
 82	case ALTR_A10SR_PWR_GOOD2_REG:
 83	case ALTR_A10SR_PWR_GOOD3_REG:
 84	case ALTR_A10SR_HPS_RST_REG:
 85	case ALTR_A10SR_I2C_M_REG:
 86	case ALTR_A10SR_WARM_RST_REG:
 87	case ALTR_A10SR_WR_KEY_REG:
 88	case ALTR_A10SR_PMBUS_REG:
 89		return true;
 90	default:
 91		return false;
 92	}
 93}
 94
 95static const struct regmap_config altr_a10sr_regmap_config = {
 96	.reg_bits = 8,
 97	.val_bits = 8,
 98
 99	.cache_type = REGCACHE_NONE,
100
101	.use_single_read = true,
102	.use_single_write = true,
103	.read_flag_mask = 1,
104	.write_flag_mask = 0,
105
106	.max_register = ALTR_A10SR_WR_KEY_REG,
107	.readable_reg = altr_a10sr_reg_readable,
108	.writeable_reg = altr_a10sr_reg_writeable,
109	.volatile_reg = altr_a10sr_reg_volatile,
110
111};
112
113static int altr_a10sr_spi_probe(struct spi_device *spi)
114{
115	int ret;
116	struct altr_a10sr *a10sr;
117
118	a10sr = devm_kzalloc(&spi->dev, sizeof(*a10sr),
119			     GFP_KERNEL);
120	if (!a10sr)
121		return -ENOMEM;
122
123	spi->mode = SPI_MODE_3;
124	spi->bits_per_word = 8;
125	spi_setup(spi);
126
127	a10sr->dev = &spi->dev;
128
129	spi_set_drvdata(spi, a10sr);
130
131	a10sr->regmap = devm_regmap_init_spi(spi, &altr_a10sr_regmap_config);
132	if (IS_ERR(a10sr->regmap)) {
133		ret = PTR_ERR(a10sr->regmap);
134		dev_err(&spi->dev, "Failed to allocate register map: %d\n",
135			ret);
136		return ret;
137	}
138
139	ret = devm_mfd_add_devices(a10sr->dev, PLATFORM_DEVID_AUTO,
140				   altr_a10sr_subdev_info,
141				   ARRAY_SIZE(altr_a10sr_subdev_info),
142				   NULL, 0, NULL);
143	if (ret)
144		dev_err(a10sr->dev, "Failed to register sub-devices: %d\n",
145			ret);
146
147	return ret;
148}
149
150static const struct of_device_id altr_a10sr_spi_of_match[] = {
151	{ .compatible = "altr,a10sr" },
152	{ },
153};
154MODULE_DEVICE_TABLE(of, altr_a10sr_spi_of_match);
155
156static const struct spi_device_id altr_a10sr_spi_ids[] = {
157	{ .name = "a10sr" },
158	{ },
159};
160MODULE_DEVICE_TABLE(spi, altr_a10sr_spi_ids);
161
162static struct spi_driver altr_a10sr_spi_driver = {
163	.probe = altr_a10sr_spi_probe,
164	.driver = {
165		.name = "altr_a10sr",
166		.of_match_table = altr_a10sr_spi_of_match,
167	},
168	.id_table = altr_a10sr_spi_ids,
169};
170builtin_driver(altr_a10sr_spi_driver, spi_register_driver)