Version:  2.0.40 2.2.26 2.4.37 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5

Linux/drivers/spi/spi-dw-mmio.c

  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 
 28 struct dw_spi_mmio {
 29         struct dw_spi  dws;
 30         struct clk     *clk;
 31 };
 32 
 33 static 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         if (!mem) {
 51                 dev_err(&pdev->dev, "no mem resource?\n");
 52                 return -EINVAL;
 53         }
 54 
 55         dws->regs = devm_ioremap_resource(&pdev->dev, mem);
 56         if (IS_ERR(dws->regs)) {
 57                 dev_err(&pdev->dev, "SPI region map failed\n");
 58                 return PTR_ERR(dws->regs);
 59         }
 60 
 61         dws->irq = platform_get_irq(pdev, 0);
 62         if (dws->irq < 0) {
 63                 dev_err(&pdev->dev, "no irq resource?\n");
 64                 return dws->irq; /* -ENXIO */
 65         }
 66 
 67         dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
 68         if (IS_ERR(dwsmmio->clk))
 69                 return PTR_ERR(dwsmmio->clk);
 70         ret = clk_prepare_enable(dwsmmio->clk);
 71         if (ret)
 72                 return ret;
 73 
 74         dws->bus_num = pdev->id;
 75 
 76         dws->max_freq = clk_get_rate(dwsmmio->clk);
 77 
 78         device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width);
 79 
 80         num_cs = 4;
 81 
 82         device_property_read_u32(&pdev->dev, "num-cs", &num_cs);
 83 
 84         dws->num_cs = num_cs;
 85 
 86         if (pdev->dev.of_node) {
 87                 int i;
 88 
 89                 for (i = 0; i < dws->num_cs; i++) {
 90                         int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
 91                                         "cs-gpios", i);
 92 
 93                         if (cs_gpio == -EPROBE_DEFER) {
 94                                 ret = cs_gpio;
 95                                 goto out;
 96                         }
 97 
 98                         if (gpio_is_valid(cs_gpio)) {
 99                                 ret = devm_gpio_request(&pdev->dev, cs_gpio,
100                                                 dev_name(&pdev->dev));
101                                 if (ret)
102                                         goto out;
103                         }
104                 }
105         }
106 
107         ret = dw_spi_add_host(&pdev->dev, dws);
108         if (ret)
109                 goto out;
110 
111         platform_set_drvdata(pdev, dwsmmio);
112         return 0;
113 
114 out:
115         clk_disable_unprepare(dwsmmio->clk);
116         return ret;
117 }
118 
119 static int dw_spi_mmio_remove(struct platform_device *pdev)
120 {
121         struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
122 
123         clk_disable_unprepare(dwsmmio->clk);
124         dw_spi_remove_host(&dwsmmio->dws);
125 
126         return 0;
127 }
128 
129 static const struct of_device_id dw_spi_mmio_of_match[] = {
130         { .compatible = "snps,dw-apb-ssi", },
131         { /* end of table */}
132 };
133 MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
134 
135 static struct platform_driver dw_spi_mmio_driver = {
136         .probe          = dw_spi_mmio_probe,
137         .remove         = dw_spi_mmio_remove,
138         .driver         = {
139                 .name   = DRIVER_NAME,
140                 .of_match_table = dw_spi_mmio_of_match,
141         },
142 };
143 module_platform_driver(dw_spi_mmio_driver);
144 
145 MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
146 MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
147 MODULE_LICENSE("GPL v2");
148 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us