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Diffstat (limited to 'drivers/memory/pl353-smc.c')
-rw-r--r--drivers/memory/pl353-smc.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/drivers/memory/pl353-smc.c b/drivers/memory/pl353-smc.c
new file mode 100644
index 000000000..d39ee7d06
--- /dev/null
+++ b/drivers/memory/pl353-smc.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM PL353 SMC driver
+ *
+ * Copyright (C) 2012 - 2018 Xilinx, Inc
+ * Author: Punnaiah Choudary Kalluri <punnaiah@xilinx.com>
+ * Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/amba/bus.h>
+
+/**
+ * struct pl353_smc_data - Private smc driver structure
+ * @memclk: Pointer to the peripheral clock
+ * @aclk: Pointer to the AXI peripheral clock
+ */
+struct pl353_smc_data {
+ struct clk *memclk;
+ struct clk *aclk;
+};
+
+static int __maybe_unused pl353_smc_suspend(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+
+ clk_disable(pl353_smc->memclk);
+ clk_disable(pl353_smc->aclk);
+
+ return 0;
+}
+
+static int __maybe_unused pl353_smc_resume(struct device *dev)
+{
+ struct pl353_smc_data *pl353_smc = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_enable(pl353_smc->aclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable axi domain clock.\n");
+ return ret;
+ }
+
+ ret = clk_enable(pl353_smc->memclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable memory clock.\n");
+ clk_disable(pl353_smc->aclk);
+ return ret;
+ }
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(pl353_smc_dev_pm_ops, pl353_smc_suspend,
+ pl353_smc_resume);
+
+static const struct of_device_id pl353_smc_supported_children[] = {
+ {
+ .compatible = "cfi-flash"
+ },
+ {
+ .compatible = "arm,pl353-nand-r2p1",
+ },
+ {}
+};
+
+static int pl353_smc_probe(struct amba_device *adev, const struct amba_id *id)
+{
+ struct device_node *of_node = adev->dev.of_node;
+ const struct of_device_id *match = NULL;
+ struct pl353_smc_data *pl353_smc;
+ struct device_node *child;
+ int err;
+
+ pl353_smc = devm_kzalloc(&adev->dev, sizeof(*pl353_smc), GFP_KERNEL);
+ if (!pl353_smc)
+ return -ENOMEM;
+
+ pl353_smc->aclk = devm_clk_get(&adev->dev, "apb_pclk");
+ if (IS_ERR(pl353_smc->aclk)) {
+ dev_err(&adev->dev, "aclk clock not found.\n");
+ return PTR_ERR(pl353_smc->aclk);
+ }
+
+ pl353_smc->memclk = devm_clk_get(&adev->dev, "memclk");
+ if (IS_ERR(pl353_smc->memclk)) {
+ dev_err(&adev->dev, "memclk clock not found.\n");
+ return PTR_ERR(pl353_smc->memclk);
+ }
+
+ err = clk_prepare_enable(pl353_smc->aclk);
+ if (err) {
+ dev_err(&adev->dev, "Unable to enable AXI clock.\n");
+ return err;
+ }
+
+ err = clk_prepare_enable(pl353_smc->memclk);
+ if (err) {
+ dev_err(&adev->dev, "Unable to enable memory clock.\n");
+ goto disable_axi_clk;
+ }
+
+ amba_set_drvdata(adev, pl353_smc);
+
+ /* Find compatible children. Only a single child is supported */
+ for_each_available_child_of_node(of_node, child) {
+ match = of_match_node(pl353_smc_supported_children, child);
+ if (!match) {
+ dev_warn(&adev->dev, "unsupported child node\n");
+ continue;
+ }
+ break;
+ }
+ if (!match) {
+ err = -ENODEV;
+ dev_err(&adev->dev, "no matching children\n");
+ goto disable_mem_clk;
+ }
+
+ of_platform_device_create(child, NULL, &adev->dev);
+ of_node_put(child);
+
+ return 0;
+
+disable_mem_clk:
+ clk_disable_unprepare(pl353_smc->memclk);
+disable_axi_clk:
+ clk_disable_unprepare(pl353_smc->aclk);
+
+ return err;
+}
+
+static void pl353_smc_remove(struct amba_device *adev)
+{
+ struct pl353_smc_data *pl353_smc = amba_get_drvdata(adev);
+
+ clk_disable_unprepare(pl353_smc->memclk);
+ clk_disable_unprepare(pl353_smc->aclk);
+}
+
+static const struct amba_id pl353_ids[] = {
+ {
+ .id = 0x00041353,
+ .mask = 0x000fffff,
+ },
+ { 0, 0 },
+};
+MODULE_DEVICE_TABLE(amba, pl353_ids);
+
+static struct amba_driver pl353_smc_driver = {
+ .drv = {
+ .owner = THIS_MODULE,
+ .name = "pl353-smc",
+ .pm = &pl353_smc_dev_pm_ops,
+ },
+ .id_table = pl353_ids,
+ .probe = pl353_smc_probe,
+ .remove = pl353_smc_remove,
+};
+
+module_amba_driver(pl353_smc_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("ARM PL353 SMC Driver");
+MODULE_LICENSE("GPL");