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Diffstat (limited to 'drivers/soc/qcom/qcom_gsbi.c')
-rw-r--r--drivers/soc/qcom/qcom_gsbi.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/drivers/soc/qcom/qcom_gsbi.c b/drivers/soc/qcom/qcom_gsbi.c
new file mode 100644
index 000000000000..447458e696a9
--- /dev/null
+++ b/drivers/soc/qcom/qcom_gsbi.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2014, The Linux foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License rev 2 and
+ * only rev 2 as published by the free Software foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or fITNESS fOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+#define GSBI_CTRL_REG 0x0000
+#define GSBI_PROTOCOL_SHIFT 4
+
+static int gsbi_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct resource *res;
+ void __iomem *base;
+ struct clk *hclk;
+ u32 mode, crci = 0;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ if (of_property_read_u32(node, "qcom,mode", &mode)) {
+ dev_err(&pdev->dev, "missing mode configuration\n");
+ return -EINVAL;
+ }
+
+ /* not required, so default to 0 if not present */
+ of_property_read_u32(node, "qcom,crci", &crci);
+
+ dev_info(&pdev->dev, "GSBI port protocol: %d crci: %d\n", mode, crci);
+
+ hclk = devm_clk_get(&pdev->dev, "iface");
+ if (IS_ERR(hclk))
+ return PTR_ERR(hclk);
+
+ clk_prepare_enable(hclk);
+
+ writel_relaxed((mode << GSBI_PROTOCOL_SHIFT) | crci,
+ base + GSBI_CTRL_REG);
+
+ /* make sure the gsbi control write is not reordered */
+ wmb();
+
+ clk_disable_unprepare(hclk);
+
+ return of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
+}
+
+static const struct of_device_id gsbi_dt_match[] = {
+ { .compatible = "qcom,gsbi-v1.0.0", },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, gsbi_dt_match);
+
+static struct platform_driver gsbi_driver = {
+ .driver = {
+ .name = "gsbi",
+ .owner = THIS_MODULE,
+ .of_match_table = gsbi_dt_match,
+ },
+ .probe = gsbi_probe,
+};
+
+module_platform_driver(gsbi_driver);
+
+MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
+MODULE_DESCRIPTION("QCOM GSBI driver");
+MODULE_LICENSE("GPL v2");