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v5.9
  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/platform_device.h>
 11#include <linux/pm_runtime.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#include <linux/reset.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	struct clk     *pclk;
 32	void           *priv;
 33	struct reset_control *rstc;
 34};
 35
 36#define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL	0x24
 37#define OCELOT_IF_SI_OWNER_OFFSET		4
 38#define JAGUAR2_IF_SI_OWNER_OFFSET		6
 39#define MSCC_IF_SI_OWNER_MASK			GENMASK(1, 0)
 40#define MSCC_IF_SI_OWNER_SISL			0
 41#define MSCC_IF_SI_OWNER_SIBM			1
 42#define MSCC_IF_SI_OWNER_SIMC			2
 43
 44#define MSCC_SPI_MST_SW_MODE			0x14
 45#define MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE	BIT(13)
 46#define MSCC_SPI_MST_SW_MODE_SW_SPI_CS(x)	(x << 5)
 47
 48/*
 49 * For Keem Bay, CTRLR0[31] is used to select controller mode.
 50 * 0: SSI is slave
 51 * 1: SSI is master
 52 */
 53#define KEEMBAY_CTRLR0_SSIC_IS_MST		BIT(31)
 54
 55struct dw_spi_mscc {
 56	struct regmap       *syscon;
 57	void __iomem        *spi_mst;
 58};
 59
 60/*
 61 * The Designware SPI controller (referred to as master in the documentation)
 62 * automatically deasserts chip select when the tx fifo is empty. The chip
 63 * selects then needs to be either driven as GPIOs or, for the first 4 using the
 64 * the SPI boot controller registers. the final chip select is an OR gate
 65 * between the Designware SPI controller and the SPI boot controller.
 66 */
 67static void dw_spi_mscc_set_cs(struct spi_device *spi, bool enable)
 68{
 69	struct dw_spi *dws = spi_master_get_devdata(spi->master);
 70	struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws);
 71	struct dw_spi_mscc *dwsmscc = dwsmmio->priv;
 72	u32 cs = spi->chip_select;
 73
 74	if (cs < 4) {
 75		u32 sw_mode = MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE;
 76
 77		if (!enable)
 78			sw_mode |= MSCC_SPI_MST_SW_MODE_SW_SPI_CS(BIT(cs));
 79
 80		writel(sw_mode, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
 81	}
 82
 83	dw_spi_set_cs(spi, enable);
 84}
 85
 86static int dw_spi_mscc_init(struct platform_device *pdev,
 87			    struct dw_spi_mmio *dwsmmio,
 88			    const char *cpu_syscon, u32 if_si_owner_offset)
 89{
 90	struct dw_spi_mscc *dwsmscc;
 91
 92	dwsmscc = devm_kzalloc(&pdev->dev, sizeof(*dwsmscc), GFP_KERNEL);
 93	if (!dwsmscc)
 94		return -ENOMEM;
 95
 96	dwsmscc->spi_mst = devm_platform_ioremap_resource(pdev, 1);
 97	if (IS_ERR(dwsmscc->spi_mst)) {
 98		dev_err(&pdev->dev, "SPI_MST region map failed\n");
 99		return PTR_ERR(dwsmscc->spi_mst);
100	}
101
102	dwsmscc->syscon = syscon_regmap_lookup_by_compatible(cpu_syscon);
103	if (IS_ERR(dwsmscc->syscon))
104		return PTR_ERR(dwsmscc->syscon);
105
106	/* Deassert all CS */
107	writel(0, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
108
109	/* Select the owner of the SI interface */
110	regmap_update_bits(dwsmscc->syscon, MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL,
111			   MSCC_IF_SI_OWNER_MASK << if_si_owner_offset,
112			   MSCC_IF_SI_OWNER_SIMC << if_si_owner_offset);
113
114	dwsmmio->dws.set_cs = dw_spi_mscc_set_cs;
115	dwsmmio->priv = dwsmscc;
116
117	/* Register hook to configure CTRLR0 */
118	dwsmmio->dws.update_cr0 = dw_spi_update_cr0;
119
120	return 0;
121}
122
123static int dw_spi_mscc_ocelot_init(struct platform_device *pdev,
124				   struct dw_spi_mmio *dwsmmio)
125{
126	return dw_spi_mscc_init(pdev, dwsmmio, "mscc,ocelot-cpu-syscon",
127				OCELOT_IF_SI_OWNER_OFFSET);
128}
129
130static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev,
131				    struct dw_spi_mmio *dwsmmio)
132{
133	return dw_spi_mscc_init(pdev, dwsmmio, "mscc,jaguar2-cpu-syscon",
134				JAGUAR2_IF_SI_OWNER_OFFSET);
135}
136
137static int dw_spi_alpine_init(struct platform_device *pdev,
138			      struct dw_spi_mmio *dwsmmio)
139{
140	dwsmmio->dws.cs_override = 1;
141
142	/* Register hook to configure CTRLR0 */
143	dwsmmio->dws.update_cr0 = dw_spi_update_cr0;
144
145	return 0;
146}
147
148static int dw_spi_dw_apb_init(struct platform_device *pdev,
149			      struct dw_spi_mmio *dwsmmio)
150{
151	/* Register hook to configure CTRLR0 */
152	dwsmmio->dws.update_cr0 = dw_spi_update_cr0;
153
154	dw_spi_dma_setup_generic(&dwsmmio->dws);
155
156	return 0;
157}
158
159static int dw_spi_dwc_ssi_init(struct platform_device *pdev,
160			       struct dw_spi_mmio *dwsmmio)
161{
162	/* Register hook to configure CTRLR0 */
163	dwsmmio->dws.update_cr0 = dw_spi_update_cr0_v1_01a;
164
165	dw_spi_dma_setup_generic(&dwsmmio->dws);
166
167	return 0;
168}
169
170static u32 dw_spi_update_cr0_keembay(struct spi_controller *master,
171				     struct spi_device *spi,
172				     struct spi_transfer *transfer)
173{
174	u32 cr0 = dw_spi_update_cr0_v1_01a(master, spi, transfer);
175
176	return cr0 | KEEMBAY_CTRLR0_SSIC_IS_MST;
177}
178
179static int dw_spi_keembay_init(struct platform_device *pdev,
180			       struct dw_spi_mmio *dwsmmio)
181{
182	/* Register hook to configure CTRLR0 */
183	dwsmmio->dws.update_cr0 = dw_spi_update_cr0_keembay;
184
185	return 0;
186}
187
188static int dw_spi_mmio_probe(struct platform_device *pdev)
189{
190	int (*init_func)(struct platform_device *pdev,
191			 struct dw_spi_mmio *dwsmmio);
192	struct dw_spi_mmio *dwsmmio;
193	struct resource *mem;
194	struct dw_spi *dws;
 
195	int ret;
196	int num_cs;
197
198	dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
199			GFP_KERNEL);
200	if (!dwsmmio)
201		return -ENOMEM;
 
202
203	dws = &dwsmmio->dws;
204
205	/* Get basic io resource and map it */
206	dws->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
207	if (IS_ERR(dws->regs))
208		return PTR_ERR(dws->regs);
209
210	dws->paddr = mem->start;
211
212	dws->irq = platform_get_irq(pdev, 0);
213	if (dws->irq < 0)
214		return dws->irq; /* -ENXIO */
215
216	dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
217	if (IS_ERR(dwsmmio->clk))
218		return PTR_ERR(dwsmmio->clk);
219	ret = clk_prepare_enable(dwsmmio->clk);
220	if (ret)
221		return ret;
222
223	/* Optional clock needed to access the registers */
224	dwsmmio->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
225	if (IS_ERR(dwsmmio->pclk)) {
226		ret = PTR_ERR(dwsmmio->pclk);
227		goto out_clk;
228	}
229	ret = clk_prepare_enable(dwsmmio->pclk);
230	if (ret)
231		goto out_clk;
232
233	/* find an optional reset controller */
234	dwsmmio->rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, "spi");
235	if (IS_ERR(dwsmmio->rstc)) {
236		ret = PTR_ERR(dwsmmio->rstc);
237		goto out_clk;
 
238	}
239	reset_control_deassert(dwsmmio->rstc);
240
241	dws->bus_num = pdev->id;
242
243	dws->max_freq = clk_get_rate(dwsmmio->clk);
244
245	device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width);
246
247	num_cs = 4;
248
249	device_property_read_u32(&pdev->dev, "num-cs", &num_cs);
250
251	dws->num_cs = num_cs;
 
 
 
 
 
252
253	init_func = device_get_match_data(&pdev->dev);
254	if (init_func) {
255		ret = init_func(pdev, dwsmmio);
256		if (ret)
257			goto out;
258	}
 
259
260	pm_runtime_enable(&pdev->dev);
 
 
 
261
262	ret = dw_spi_add_host(&pdev->dev, dws);
263	if (ret)
264		goto out;
265
266	platform_set_drvdata(pdev, dwsmmio);
267	return 0;
268
269out:
270	pm_runtime_disable(&pdev->dev);
271	clk_disable_unprepare(dwsmmio->pclk);
272out_clk:
273	clk_disable_unprepare(dwsmmio->clk);
274	reset_control_assert(dwsmmio->rstc);
275
 
 
 
 
 
 
276	return ret;
277}
278
279static int dw_spi_mmio_remove(struct platform_device *pdev)
280{
281	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
 
 
 
282
 
 
 
 
 
283	dw_spi_remove_host(&dwsmmio->dws);
284	pm_runtime_disable(&pdev->dev);
285	clk_disable_unprepare(dwsmmio->pclk);
286	clk_disable_unprepare(dwsmmio->clk);
287	reset_control_assert(dwsmmio->rstc);
288
 
 
289	return 0;
290}
291
292static const struct of_device_id dw_spi_mmio_of_match[] = {
293	{ .compatible = "snps,dw-apb-ssi", .data = dw_spi_dw_apb_init},
294	{ .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init},
295	{ .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init},
296	{ .compatible = "amazon,alpine-dw-apb-ssi", .data = dw_spi_alpine_init},
297	{ .compatible = "renesas,rzn1-spi", .data = dw_spi_dw_apb_init},
298	{ .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_dwc_ssi_init},
299	{ .compatible = "intel,keembay-ssi", .data = dw_spi_keembay_init},
300	{ /* end of table */}
301};
302MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
303
304#ifdef CONFIG_ACPI
305static const struct acpi_device_id dw_spi_mmio_acpi_match[] = {
306	{"HISI0173", (kernel_ulong_t)dw_spi_dw_apb_init},
307	{},
308};
309MODULE_DEVICE_TABLE(acpi, dw_spi_mmio_acpi_match);
310#endif
311
312static struct platform_driver dw_spi_mmio_driver = {
313	.probe		= dw_spi_mmio_probe,
314	.remove		= dw_spi_mmio_remove,
315	.driver		= {
316		.name	= DRIVER_NAME,
317		.of_match_table = dw_spi_mmio_of_match,
318		.acpi_match_table = ACPI_PTR(dw_spi_mmio_acpi_match),
319	},
320};
321module_platform_driver(dw_spi_mmio_driver);
 
 
 
 
 
 
 
 
 
 
 
322
323MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
324MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
325MODULE_LICENSE("GPL v2");
v3.1
 
  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
 19#include "spi-dw.h"
 20
 21#define DRIVER_NAME "dw_spi_mmio"
 22
 23struct dw_spi_mmio {
 24	struct dw_spi  dws;
 25	struct clk     *clk;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 26};
 27
 28static int __devinit dw_spi_mmio_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 29{
 
 
 
 
 
 
 
 
 
 
 30	struct dw_spi_mmio *dwsmmio;
 
 31	struct dw_spi *dws;
 32	struct resource *mem, *ioarea;
 33	int ret;
 
 34
 35	dwsmmio = kzalloc(sizeof(struct dw_spi_mmio), GFP_KERNEL);
 36	if (!dwsmmio) {
 37		ret = -ENOMEM;
 38		goto err_end;
 39	}
 40
 41	dws = &dwsmmio->dws;
 42
 43	/* Get basic io resource and map it */
 44	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 45	if (!mem) {
 46		dev_err(&pdev->dev, "no mem resource?\n");
 47		ret = -EINVAL;
 48		goto err_kfree;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 49	}
 
 
 
 50
 51	ioarea = request_mem_region(mem->start, resource_size(mem),
 52			pdev->name);
 53	if (!ioarea) {
 54		dev_err(&pdev->dev, "SPI region already claimed\n");
 55		ret = -EBUSY;
 56		goto err_kfree;
 57	}
 
 58
 59	dws->regs = ioremap_nocache(mem->start, resource_size(mem));
 60	if (!dws->regs) {
 61		dev_err(&pdev->dev, "SPI region already mapped\n");
 62		ret = -ENOMEM;
 63		goto err_release_reg;
 64	}
 
 
 
 65
 66	dws->irq = platform_get_irq(pdev, 0);
 67	if (dws->irq < 0) {
 68		dev_err(&pdev->dev, "no irq resource?\n");
 69		ret = dws->irq; /* -ENXIO */
 70		goto err_unmap;
 71	}
 72
 73	dwsmmio->clk = clk_get(&pdev->dev, NULL);
 74	if (IS_ERR(dwsmmio->clk)) {
 75		ret = PTR_ERR(dwsmmio->clk);
 76		goto err_irq;
 
 77	}
 78	clk_enable(dwsmmio->clk);
 79
 80	dws->parent_dev = &pdev->dev;
 81	dws->bus_num = 0;
 82	dws->num_cs = 4;
 83	dws->max_freq = clk_get_rate(dwsmmio->clk);
 84
 85	ret = dw_spi_add_host(dws);
 86	if (ret)
 87		goto err_clk;
 88
 89	platform_set_drvdata(pdev, dwsmmio);
 90	return 0;
 91
 92err_clk:
 93	clk_disable(dwsmmio->clk);
 94	clk_put(dwsmmio->clk);
 95	dwsmmio->clk = NULL;
 96err_irq:
 97	free_irq(dws->irq, dws);
 98err_unmap:
 99	iounmap(dws->regs);
100err_release_reg:
101	release_mem_region(mem->start, resource_size(mem));
102err_kfree:
103	kfree(dwsmmio);
104err_end:
105	return ret;
106}
107
108static int __devexit dw_spi_mmio_remove(struct platform_device *pdev)
109{
110	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
111	struct resource *mem;
112
113	platform_set_drvdata(pdev, NULL);
114
115	clk_disable(dwsmmio->clk);
116	clk_put(dwsmmio->clk);
117	dwsmmio->clk = NULL;
118
119	free_irq(dwsmmio->dws.irq, &dwsmmio->dws);
120	dw_spi_remove_host(&dwsmmio->dws);
121	iounmap(dwsmmio->dws.regs);
122	kfree(dwsmmio);
 
 
123
124	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
125	release_mem_region(mem->start, resource_size(mem));
126	return 0;
127}
128
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
129static struct platform_driver dw_spi_mmio_driver = {
130	.remove		= __devexit_p(dw_spi_mmio_remove),
 
131	.driver		= {
132		.name	= DRIVER_NAME,
133		.owner	= THIS_MODULE,
 
134	},
135};
136
137static int __init dw_spi_mmio_init(void)
138{
139	return platform_driver_probe(&dw_spi_mmio_driver, dw_spi_mmio_probe);
140}
141module_init(dw_spi_mmio_init);
142
143static void __exit dw_spi_mmio_exit(void)
144{
145	platform_driver_unregister(&dw_spi_mmio_driver);
146}
147module_exit(dw_spi_mmio_exit);
148
149MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
150MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
151MODULE_LICENSE("GPL v2");