summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/spi/spi-dw-mmio.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/drivers/spi/spi-dw-mmio.c')
-rw-r--r--kernel/drivers/spi/spi-dw-mmio.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/kernel/drivers/spi/spi-dw-mmio.c b/kernel/drivers/spi/spi-dw-mmio.c
new file mode 100644
index 000000000..eb03e1215
--- /dev/null
+++ b/kernel/drivers/spi/spi-dw-mmio.c
@@ -0,0 +1,145 @@
+/*
+ * Memory-mapped interface driver for DW SPI Core
+ *
+ * Copyright (c) 2010, Octasic semiconductor.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/scatterlist.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+
+#include "spi-dw.h"
+
+#define DRIVER_NAME "dw_spi_mmio"
+
+struct dw_spi_mmio {
+ struct dw_spi dws;
+ struct clk *clk;
+};
+
+static int dw_spi_mmio_probe(struct platform_device *pdev)
+{
+ struct dw_spi_mmio *dwsmmio;
+ struct dw_spi *dws;
+ struct resource *mem;
+ int ret;
+ int num_cs;
+
+ dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
+ GFP_KERNEL);
+ if (!dwsmmio)
+ return -ENOMEM;
+
+ dws = &dwsmmio->dws;
+
+ /* Get basic io resource and map it */
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem) {
+ dev_err(&pdev->dev, "no mem resource?\n");
+ return -EINVAL;
+ }
+
+ dws->regs = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(dws->regs)) {
+ dev_err(&pdev->dev, "SPI region map failed\n");
+ return PTR_ERR(dws->regs);
+ }
+
+ dws->irq = platform_get_irq(pdev, 0);
+ if (dws->irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return dws->irq; /* -ENXIO */
+ }
+
+ dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(dwsmmio->clk))
+ return PTR_ERR(dwsmmio->clk);
+ ret = clk_prepare_enable(dwsmmio->clk);
+ if (ret)
+ return ret;
+
+ dws->bus_num = pdev->id;
+
+ dws->max_freq = clk_get_rate(dwsmmio->clk);
+
+ num_cs = 4;
+
+ if (pdev->dev.of_node)
+ of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs);
+
+ dws->num_cs = num_cs;
+
+ if (pdev->dev.of_node) {
+ int i;
+
+ for (i = 0; i < dws->num_cs; i++) {
+ int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+ "cs-gpios", i);
+
+ if (cs_gpio == -EPROBE_DEFER) {
+ ret = cs_gpio;
+ goto out;
+ }
+
+ if (gpio_is_valid(cs_gpio)) {
+ ret = devm_gpio_request(&pdev->dev, cs_gpio,
+ dev_name(&pdev->dev));
+ if (ret)
+ goto out;
+ }
+ }
+ }
+
+ ret = dw_spi_add_host(&pdev->dev, dws);
+ if (ret)
+ goto out;
+
+ platform_set_drvdata(pdev, dwsmmio);
+ return 0;
+
+out:
+ clk_disable_unprepare(dwsmmio->clk);
+ return ret;
+}
+
+static int dw_spi_mmio_remove(struct platform_device *pdev)
+{
+ struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(dwsmmio->clk);
+ dw_spi_remove_host(&dwsmmio->dws);
+
+ return 0;
+}
+
+static const struct of_device_id dw_spi_mmio_of_match[] = {
+ { .compatible = "snps,dw-apb-ssi", },
+ { /* end of table */}
+};
+MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
+
+static struct platform_driver dw_spi_mmio_driver = {
+ .probe = dw_spi_mmio_probe,
+ .remove = dw_spi_mmio_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = dw_spi_mmio_of_match,
+ },
+};
+module_platform_driver(dw_spi_mmio_driver);
+
+MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
+MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
+MODULE_LICENSE("GPL v2");