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192.168.1.100 / T103 / 97e9fac9a4af53fd898b9d7343d16c479961ca41 / . / src / kernel / linux / v4.14 / drivers / spi / spi-dw-mmio.c
blob: d25cc4037e239d0df386a06253049dd25a79b2b2 [file] [log] [blame]
rjw1f884582022-01-06 17:20:42 +0800[diff] [blame]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 dw_spi_remove_host(&dwsmmio->dws);
119 clk_disable_unprepare(dwsmmio->clk);
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");