aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/clk/qcom/apcs-msm8916.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/clk/qcom/apcs-msm8916.c')
-rw-r--r--drivers/clk/qcom/apcs-msm8916.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/drivers/clk/qcom/apcs-msm8916.c b/drivers/clk/qcom/apcs-msm8916.c
new file mode 100644
index 000000000000..246957f1a413
--- /dev/null
+++ b/drivers/clk/qcom/apcs-msm8916.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Qualcomm APCS clock controller driver
+ *
+ * Copyright (c) 2017, Linaro Limited
+ * Author: Georgi Djakov <georgi.djakov@linaro.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "clk-regmap.h"
+#include "clk-regmap-mux-div.h"
+
+static const u32 gpll0_a53cc_map[] = { 4, 5 };
+
+static const char * const gpll0_a53cc[] = {
+ "gpll0_vote",
+ "a53pll",
+};
+
+/*
+ * We use the notifier function for switching to a temporary safe configuration
+ * (mux and divider), while the A53 PLL is reconfigured.
+ */
+static int a53cc_notifier_cb(struct notifier_block *nb, unsigned long event,
+ void *data)
+{
+ int ret = 0;
+ struct clk_regmap_mux_div *md = container_of(nb,
+ struct clk_regmap_mux_div,
+ clk_nb);
+ if (event == PRE_RATE_CHANGE)
+ /* set the mux and divider to safe frequency (400mhz) */
+ ret = mux_div_set_src_div(md, 4, 3);
+
+ return notifier_from_errno(ret);
+}
+
+static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device *parent = dev->parent;
+ struct clk_regmap_mux_div *a53cc;
+ struct regmap *regmap;
+ struct clk_init_data init = { };
+ int ret;
+
+ regmap = dev_get_regmap(parent, NULL);
+ if (IS_ERR(regmap)) {
+ ret = PTR_ERR(regmap);
+ dev_err(dev, "failed to get regmap: %d\n", ret);
+ return ret;
+ }
+
+ a53cc = devm_kzalloc(dev, sizeof(*a53cc), GFP_KERNEL);
+ if (!a53cc)
+ return -ENOMEM;
+
+ init.name = "a53mux";
+ init.parent_names = gpll0_a53cc;
+ init.num_parents = ARRAY_SIZE(gpll0_a53cc);
+ init.ops = &clk_regmap_mux_div_ops;
+ init.flags = CLK_SET_RATE_PARENT;
+
+ a53cc->clkr.hw.init = &init;
+ a53cc->clkr.regmap = regmap;
+ a53cc->reg_offset = 0x50;
+ a53cc->hid_width = 5;
+ a53cc->hid_shift = 0;
+ a53cc->src_width = 3;
+ a53cc->src_shift = 8;
+ a53cc->parent_map = gpll0_a53cc_map;
+
+ a53cc->pclk = devm_clk_get(parent, NULL);
+ if (IS_ERR(a53cc->pclk)) {
+ ret = PTR_ERR(a53cc->pclk);
+ dev_err(dev, "failed to get clk: %d\n", ret);
+ return ret;
+ }
+
+ a53cc->clk_nb.notifier_call = a53cc_notifier_cb;
+ ret = clk_notifier_register(a53cc->pclk, &a53cc->clk_nb);
+ if (ret) {
+ dev_err(dev, "failed to register clock notifier: %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_clk_register_regmap(dev, &a53cc->clkr);
+ if (ret) {
+ dev_err(dev, "failed to register regmap clock: %d\n", ret);
+ goto err;
+ }
+
+ ret = of_clk_add_hw_provider(parent->of_node, of_clk_hw_simple_get,
+ &a53cc->clkr.hw);
+ if (ret) {
+ dev_err(dev, "failed to add clock provider: %d\n", ret);
+ goto err;
+ }
+
+ platform_set_drvdata(pdev, a53cc);
+
+ return 0;
+
+err:
+ clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
+ return ret;
+}
+
+static int qcom_apcs_msm8916_clk_remove(struct platform_device *pdev)
+{
+ struct clk_regmap_mux_div *a53cc = platform_get_drvdata(pdev);
+ struct device *parent = pdev->dev.parent;
+
+ clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
+ of_clk_del_provider(parent->of_node);
+
+ return 0;
+}
+
+static struct platform_driver qcom_apcs_msm8916_clk_driver = {
+ .probe = qcom_apcs_msm8916_clk_probe,
+ .remove = qcom_apcs_msm8916_clk_remove,
+ .driver = {
+ .name = "qcom-apcs-msm8916-clk",
+ },
+};
+module_platform_driver(qcom_apcs_msm8916_clk_driver);
+
+MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Qualcomm MSM8916 APCS clock driver");