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v4.6
 
  1/*
  2 * Memory-mapped interface driver for DW SPI Core
  3 *
  4 * Copyright (c) 2010, Octasic semiconductor.
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms and conditions of the GNU General Public License,
  8 * version 2, as published by the Free Software Foundation.
  9 */
 10
 11#include <linux/clk.h>
 12#include <linux/err.h>
 13#include <linux/interrupt.h>
 14#include <linux/platform_device.h>
 15#include <linux/slab.h>
 16#include <linux/spi/spi.h>
 17#include <linux/scatterlist.h>
 
 18#include <linux/module.h>
 19#include <linux/of.h>
 20#include <linux/of_gpio.h>
 21#include <linux/of_platform.h>
 
 22#include <linux/property.h>
 
 23
 24#include "spi-dw.h"
 25
 26#define DRIVER_NAME "dw_spi_mmio"
 27
 28struct dw_spi_mmio {
 29	struct dw_spi  dws;
 30	struct clk     *clk;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31};
 32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33static int dw_spi_mmio_probe(struct platform_device *pdev)
 34{
 
 
 35	struct dw_spi_mmio *dwsmmio;
 36	struct dw_spi *dws;
 37	struct resource *mem;
 38	int ret;
 39	int num_cs;
 40
 41	dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
 42			GFP_KERNEL);
 43	if (!dwsmmio)
 44		return -ENOMEM;
 45
 46	dws = &dwsmmio->dws;
 47
 48	/* Get basic io resource and map it */
 49	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 50	dws->regs = devm_ioremap_resource(&pdev->dev, mem);
 51	if (IS_ERR(dws->regs)) {
 52		dev_err(&pdev->dev, "SPI region map failed\n");
 53		return PTR_ERR(dws->regs);
 54	}
 55
 56	dws->irq = platform_get_irq(pdev, 0);
 57	if (dws->irq < 0) {
 58		dev_err(&pdev->dev, "no irq resource?\n");
 59		return dws->irq; /* -ENXIO */
 60	}
 61
 62	dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
 63	if (IS_ERR(dwsmmio->clk))
 64		return PTR_ERR(dwsmmio->clk);
 65	ret = clk_prepare_enable(dwsmmio->clk);
 66	if (ret)
 67		return ret;
 68
 
 
 
 
 
 
 
 
 
 
 69	dws->bus_num = pdev->id;
 70
 71	dws->max_freq = clk_get_rate(dwsmmio->clk);
 72
 73	device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width);
 74
 75	num_cs = 4;
 76
 77	device_property_read_u32(&pdev->dev, "num-cs", &num_cs);
 78
 79	dws->num_cs = num_cs;
 80
 81	if (pdev->dev.of_node) {
 82		int i;
 83
 84		for (i = 0; i < dws->num_cs; i++) {
 85			int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
 86					"cs-gpios", i);
 87
 88			if (cs_gpio == -EPROBE_DEFER) {
 89				ret = cs_gpio;
 90				goto out;
 91			}
 92
 93			if (gpio_is_valid(cs_gpio)) {
 94				ret = devm_gpio_request(&pdev->dev, cs_gpio,
 95						dev_name(&pdev->dev));
 96				if (ret)
 97					goto out;
 98			}
 99		}
100	}
101
102	ret = dw_spi_add_host(&pdev->dev, dws);
103	if (ret)
104		goto out;
105
106	platform_set_drvdata(pdev, dwsmmio);
107	return 0;
108
109out:
 
 
110	clk_disable_unprepare(dwsmmio->clk);
111	return ret;
112}
113
114static int dw_spi_mmio_remove(struct platform_device *pdev)
115{
116	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
117
118	clk_disable_unprepare(dwsmmio->clk);
119	dw_spi_remove_host(&dwsmmio->dws);
 
 
120
121	return 0;
122}
123
124static const struct of_device_id dw_spi_mmio_of_match[] = {
125	{ .compatible = "snps,dw-apb-ssi", },
 
 
 
126	{ /* end of table */}
127};
128MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
129
 
 
 
 
 
 
130static struct platform_driver dw_spi_mmio_driver = {
131	.probe		= dw_spi_mmio_probe,
132	.remove		= dw_spi_mmio_remove,
133	.driver		= {
134		.name	= DRIVER_NAME,
135		.of_match_table = dw_spi_mmio_of_match,
 
136	},
137};
138module_platform_driver(dw_spi_mmio_driver);
139
140MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
141MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
142MODULE_LICENSE("GPL v2");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Memory-mapped interface driver for DW SPI Core
  4 *
  5 * Copyright (c) 2010, Octasic semiconductor.
 
 
 
 
  6 */
  7
  8#include <linux/clk.h>
  9#include <linux/err.h>
 10#include <linux/interrupt.h>
 11#include <linux/platform_device.h>
 12#include <linux/slab.h>
 13#include <linux/spi/spi.h>
 14#include <linux/scatterlist.h>
 15#include <linux/mfd/syscon.h>
 16#include <linux/module.h>
 17#include <linux/of.h>
 
 18#include <linux/of_platform.h>
 19#include <linux/acpi.h>
 20#include <linux/property.h>
 21#include <linux/regmap.h>
 22
 23#include "spi-dw.h"
 24
 25#define DRIVER_NAME "dw_spi_mmio"
 26
 27struct dw_spi_mmio {
 28	struct dw_spi  dws;
 29	struct clk     *clk;
 30	struct clk     *pclk;
 31	void           *priv;
 32};
 33
 34#define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL	0x24
 35#define OCELOT_IF_SI_OWNER_OFFSET		4
 36#define JAGUAR2_IF_SI_OWNER_OFFSET		6
 37#define MSCC_IF_SI_OWNER_MASK			GENMASK(1, 0)
 38#define MSCC_IF_SI_OWNER_SISL			0
 39#define MSCC_IF_SI_OWNER_SIBM			1
 40#define MSCC_IF_SI_OWNER_SIMC			2
 41
 42#define MSCC_SPI_MST_SW_MODE			0x14
 43#define MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE	BIT(13)
 44#define MSCC_SPI_MST_SW_MODE_SW_SPI_CS(x)	(x << 5)
 45
 46struct dw_spi_mscc {
 47	struct regmap       *syscon;
 48	void __iomem        *spi_mst;
 49};
 50
 51/*
 52 * The Designware SPI controller (referred to as master in the documentation)
 53 * automatically deasserts chip select when the tx fifo is empty. The chip
 54 * selects then needs to be either driven as GPIOs or, for the first 4 using the
 55 * the SPI boot controller registers. the final chip select is an OR gate
 56 * between the Designware SPI controller and the SPI boot controller.
 57 */
 58static void dw_spi_mscc_set_cs(struct spi_device *spi, bool enable)
 59{
 60	struct dw_spi *dws = spi_master_get_devdata(spi->master);
 61	struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws);
 62	struct dw_spi_mscc *dwsmscc = dwsmmio->priv;
 63	u32 cs = spi->chip_select;
 64
 65	if (cs < 4) {
 66		u32 sw_mode = MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE;
 67
 68		if (!enable)
 69			sw_mode |= MSCC_SPI_MST_SW_MODE_SW_SPI_CS(BIT(cs));
 70
 71		writel(sw_mode, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
 72	}
 73
 74	dw_spi_set_cs(spi, enable);
 75}
 76
 77static int dw_spi_mscc_init(struct platform_device *pdev,
 78			    struct dw_spi_mmio *dwsmmio,
 79			    const char *cpu_syscon, u32 if_si_owner_offset)
 80{
 81	struct dw_spi_mscc *dwsmscc;
 82
 83	dwsmscc = devm_kzalloc(&pdev->dev, sizeof(*dwsmscc), GFP_KERNEL);
 84	if (!dwsmscc)
 85		return -ENOMEM;
 86
 87	dwsmscc->spi_mst = devm_platform_ioremap_resource(pdev, 1);
 88	if (IS_ERR(dwsmscc->spi_mst)) {
 89		dev_err(&pdev->dev, "SPI_MST region map failed\n");
 90		return PTR_ERR(dwsmscc->spi_mst);
 91	}
 92
 93	dwsmscc->syscon = syscon_regmap_lookup_by_compatible(cpu_syscon);
 94	if (IS_ERR(dwsmscc->syscon))
 95		return PTR_ERR(dwsmscc->syscon);
 96
 97	/* Deassert all CS */
 98	writel(0, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
 99
100	/* Select the owner of the SI interface */
101	regmap_update_bits(dwsmscc->syscon, MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL,
102			   MSCC_IF_SI_OWNER_MASK << if_si_owner_offset,
103			   MSCC_IF_SI_OWNER_SIMC << if_si_owner_offset);
104
105	dwsmmio->dws.set_cs = dw_spi_mscc_set_cs;
106	dwsmmio->priv = dwsmscc;
107
108	return 0;
109}
110
111static int dw_spi_mscc_ocelot_init(struct platform_device *pdev,
112				   struct dw_spi_mmio *dwsmmio)
113{
114	return dw_spi_mscc_init(pdev, dwsmmio, "mscc,ocelot-cpu-syscon",
115				OCELOT_IF_SI_OWNER_OFFSET);
116}
117
118static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev,
119				    struct dw_spi_mmio *dwsmmio)
120{
121	return dw_spi_mscc_init(pdev, dwsmmio, "mscc,jaguar2-cpu-syscon",
122				JAGUAR2_IF_SI_OWNER_OFFSET);
123}
124
125static int dw_spi_alpine_init(struct platform_device *pdev,
126			      struct dw_spi_mmio *dwsmmio)
127{
128	dwsmmio->dws.cs_override = 1;
129
130	return 0;
131}
132
133static int dw_spi_mmio_probe(struct platform_device *pdev)
134{
135	int (*init_func)(struct platform_device *pdev,
136			 struct dw_spi_mmio *dwsmmio);
137	struct dw_spi_mmio *dwsmmio;
138	struct dw_spi *dws;
 
139	int ret;
140	int num_cs;
141
142	dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
143			GFP_KERNEL);
144	if (!dwsmmio)
145		return -ENOMEM;
146
147	dws = &dwsmmio->dws;
148
149	/* Get basic io resource and map it */
150	dws->regs = devm_platform_ioremap_resource(pdev, 0);
 
151	if (IS_ERR(dws->regs)) {
152		dev_err(&pdev->dev, "SPI region map failed\n");
153		return PTR_ERR(dws->regs);
154	}
155
156	dws->irq = platform_get_irq(pdev, 0);
157	if (dws->irq < 0)
 
158		return dws->irq; /* -ENXIO */
 
159
160	dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
161	if (IS_ERR(dwsmmio->clk))
162		return PTR_ERR(dwsmmio->clk);
163	ret = clk_prepare_enable(dwsmmio->clk);
164	if (ret)
165		return ret;
166
167	/* Optional clock needed to access the registers */
168	dwsmmio->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
169	if (IS_ERR(dwsmmio->pclk)) {
170		ret = PTR_ERR(dwsmmio->pclk);
171		goto out_clk;
172	}
173	ret = clk_prepare_enable(dwsmmio->pclk);
174	if (ret)
175		goto out_clk;
176
177	dws->bus_num = pdev->id;
178
179	dws->max_freq = clk_get_rate(dwsmmio->clk);
180
181	device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width);
182
183	num_cs = 4;
184
185	device_property_read_u32(&pdev->dev, "num-cs", &num_cs);
186
187	dws->num_cs = num_cs;
188
189	init_func = device_get_match_data(&pdev->dev);
190	if (init_func) {
191		ret = init_func(pdev, dwsmmio);
192		if (ret)
193			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
194	}
195
196	ret = dw_spi_add_host(&pdev->dev, dws);
197	if (ret)
198		goto out;
199
200	platform_set_drvdata(pdev, dwsmmio);
201	return 0;
202
203out:
204	clk_disable_unprepare(dwsmmio->pclk);
205out_clk:
206	clk_disable_unprepare(dwsmmio->clk);
207	return ret;
208}
209
210static int dw_spi_mmio_remove(struct platform_device *pdev)
211{
212	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
213
 
214	dw_spi_remove_host(&dwsmmio->dws);
215	clk_disable_unprepare(dwsmmio->pclk);
216	clk_disable_unprepare(dwsmmio->clk);
217
218	return 0;
219}
220
221static const struct of_device_id dw_spi_mmio_of_match[] = {
222	{ .compatible = "snps,dw-apb-ssi", },
223	{ .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init},
224	{ .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init},
225	{ .compatible = "amazon,alpine-dw-apb-ssi", .data = dw_spi_alpine_init},
226	{ /* end of table */}
227};
228MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
229
230static const struct acpi_device_id dw_spi_mmio_acpi_match[] = {
231	{"HISI0173", 0},
232	{},
233};
234MODULE_DEVICE_TABLE(acpi, dw_spi_mmio_acpi_match);
235
236static struct platform_driver dw_spi_mmio_driver = {
237	.probe		= dw_spi_mmio_probe,
238	.remove		= dw_spi_mmio_remove,
239	.driver		= {
240		.name	= DRIVER_NAME,
241		.of_match_table = dw_spi_mmio_of_match,
242		.acpi_match_table = ACPI_PTR(dw_spi_mmio_acpi_match),
243	},
244};
245module_platform_driver(dw_spi_mmio_driver);
246
247MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
248MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
249MODULE_LICENSE("GPL v2");