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Diffstat (limited to 'drivers/spi/spi-altera-platform.c')
-rw-r--r--drivers/spi/spi-altera-platform.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/drivers/spi/spi-altera-platform.c b/drivers/spi/spi-altera-platform.c
new file mode 100644
index 0000000000..72e7a0f217
--- /dev/null
+++ b/drivers/spi/spi-altera-platform.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Altera SPI driver
+ *
+ * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Based on spi_s3c24xx.c, which is:
+ * Copyright (c) 2006 Ben Dooks
+ * Copyright (c) 2006 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spi/altera.h>
+#include <linux/spi/spi.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#define DRV_NAME "spi_altera"
+
+enum altera_spi_type {
+ ALTERA_SPI_TYPE_UNKNOWN,
+ ALTERA_SPI_TYPE_SUBDEV,
+};
+
+static const struct regmap_config spi_altera_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
+};
+
+static int altera_spi_probe(struct platform_device *pdev)
+{
+ const struct platform_device_id *platid = platform_get_device_id(pdev);
+ struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ enum altera_spi_type type = ALTERA_SPI_TYPE_UNKNOWN;
+ struct altera_spi *hw;
+ struct spi_controller *host;
+ int err = -ENODEV;
+ u16 i;
+
+ host = spi_alloc_host(&pdev->dev, sizeof(struct altera_spi));
+ if (!host)
+ return err;
+
+ /* setup the host state. */
+ host->bus_num = -1;
+
+ if (pdata) {
+ if (pdata->num_chipselect > ALTERA_SPI_MAX_CS) {
+ dev_err(&pdev->dev,
+ "Invalid number of chipselect: %u\n",
+ pdata->num_chipselect);
+ err = -EINVAL;
+ goto exit;
+ }
+
+ host->num_chipselect = pdata->num_chipselect;
+ host->mode_bits = pdata->mode_bits;
+ host->bits_per_word_mask = pdata->bits_per_word_mask;
+ } else {
+ host->num_chipselect = 16;
+ host->mode_bits = SPI_CS_HIGH;
+ host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
+ }
+
+ host->dev.of_node = pdev->dev.of_node;
+
+ hw = spi_controller_get_devdata(host);
+ hw->dev = &pdev->dev;
+
+ if (platid)
+ type = platid->driver_data;
+
+ /* find and map our resources */
+ if (type == ALTERA_SPI_TYPE_SUBDEV) {
+ struct resource *regoff;
+
+ hw->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!hw->regmap) {
+ dev_err(&pdev->dev, "get regmap failed\n");
+ goto exit;
+ }
+
+ regoff = platform_get_resource(pdev, IORESOURCE_REG, 0);
+ if (regoff)
+ hw->regoff = regoff->start;
+ } else {
+ void __iomem *res;
+
+ res = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(res)) {
+ err = PTR_ERR(res);
+ goto exit;
+ }
+
+ hw->regmap = devm_regmap_init_mmio(&pdev->dev, res,
+ &spi_altera_config);
+ if (IS_ERR(hw->regmap)) {
+ dev_err(&pdev->dev, "regmap mmio init failed\n");
+ err = PTR_ERR(hw->regmap);
+ goto exit;
+ }
+ }
+
+ altera_spi_init_host(host);
+
+ /* irq is optional */
+ hw->irq = platform_get_irq(pdev, 0);
+ if (hw->irq >= 0) {
+ err = devm_request_irq(&pdev->dev, hw->irq, altera_spi_irq, 0,
+ pdev->name, host);
+ if (err)
+ goto exit;
+ }
+
+ err = devm_spi_register_controller(&pdev->dev, host);
+ if (err)
+ goto exit;
+
+ if (pdata) {
+ for (i = 0; i < pdata->num_devices; i++) {
+ if (!spi_new_device(host, pdata->devices + i))
+ dev_warn(&pdev->dev,
+ "unable to create SPI device: %s\n",
+ pdata->devices[i].modalias);
+ }
+ }
+
+ dev_info(&pdev->dev, "regoff %u, irq %d\n", hw->regoff, hw->irq);
+
+ return 0;
+exit:
+ spi_controller_put(host);
+ return err;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id altera_spi_match[] = {
+ { .compatible = "ALTR,spi-1.0", },
+ { .compatible = "altr,spi-1.0", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, altera_spi_match);
+#endif /* CONFIG_OF */
+
+static const struct platform_device_id altera_spi_ids[] = {
+ { DRV_NAME, ALTERA_SPI_TYPE_UNKNOWN },
+ { "subdev_spi_altera", ALTERA_SPI_TYPE_SUBDEV },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, altera_spi_ids);
+
+static struct platform_driver altera_spi_driver = {
+ .probe = altera_spi_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .pm = NULL,
+ .of_match_table = of_match_ptr(altera_spi_match),
+ },
+ .id_table = altera_spi_ids,
+};
+module_platform_driver(altera_spi_driver);
+
+MODULE_DESCRIPTION("Altera SPI driver");
+MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);