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authorHans de Goede <hdegoede@redhat.com>2014-02-07 16:21:49 +0100
committerEmilio López <emilio@elopez.com.ar>2014-02-18 09:29:10 -0300
commitcfb0086dca781ac7ab9b63e6c8088064c29a4118 (patch)
tree85af45f1bed14802f4942c433c1772a4aed1752f /drivers/clk
parent97e36b3ce3106988b82e1ca53b1d1c872bde855a (diff)
downloadop-kernel-dev-cfb0086dca781ac7ab9b63e6c8088064c29a4118.zip
op-kernel-dev-cfb0086dca781ac7ab9b63e6c8088064c29a4118.tar.gz
clk: sunxi: Add support for USB clock-register reset bits
The usb-clk register is special in that it not only contains clk gate bits, but also has a few reset bits. This commit adds support for this by allowing gates type sunxi clks to also register a reset controller. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Emilio López <emilio@elopez.com.ar>
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/sunxi/clk-sunxi.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index 736fb60..23beb6e 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -18,6 +18,7 @@
#include <linux/clkdev.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/reset-controller.h>
#include "clk-factors.h"
@@ -688,6 +689,59 @@ static void __init sunxi_divider_clk_setup(struct device_node *node,
/**
+ * sunxi_gates_reset... - reset bits in leaf gate clk registers handling
+ */
+
+struct gates_reset_data {
+ void __iomem *reg;
+ spinlock_t *lock;
+ struct reset_controller_dev rcdev;
+};
+
+static int sunxi_gates_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct gates_reset_data *data = container_of(rcdev,
+ struct gates_reset_data,
+ rcdev);
+ unsigned long flags;
+ u32 reg;
+
+ spin_lock_irqsave(data->lock, flags);
+
+ reg = readl(data->reg);
+ writel(reg & ~BIT(id), data->reg);
+
+ spin_unlock_irqrestore(data->lock, flags);
+
+ return 0;
+}
+
+static int sunxi_gates_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct gates_reset_data *data = container_of(rcdev,
+ struct gates_reset_data,
+ rcdev);
+ unsigned long flags;
+ u32 reg;
+
+ spin_lock_irqsave(data->lock, flags);
+
+ reg = readl(data->reg);
+ writel(reg | BIT(id), data->reg);
+
+ spin_unlock_irqrestore(data->lock, flags);
+
+ return 0;
+}
+
+static struct reset_control_ops sunxi_gates_reset_ops = {
+ .assert = sunxi_gates_reset_assert,
+ .deassert = sunxi_gates_reset_deassert,
+};
+
+/**
* sunxi_gates_clk_setup() - Setup function for leaf gates on clocks
*/
@@ -695,6 +749,7 @@ static void __init sunxi_divider_clk_setup(struct device_node *node,
struct gates_data {
DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE);
+ u32 reset_mask;
};
static const struct gates_data sun4i_axi_gates_data __initconst = {
@@ -765,6 +820,7 @@ static void __init sunxi_gates_clk_setup(struct device_node *node,
struct gates_data *data)
{
struct clk_onecell_data *clk_data;
+ struct gates_reset_data *reset_data;
const char *clk_parent;
const char *clk_name;
void *reg;
@@ -808,6 +864,21 @@ static void __init sunxi_gates_clk_setup(struct device_node *node,
clk_data->clk_num = i;
of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
+
+ /* Register a reset controler for gates with reset bits */
+ if (data->reset_mask == 0)
+ return;
+
+ reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
+ if (!reset_data)
+ return;
+
+ reset_data->reg = reg;
+ reset_data->lock = &clk_lock;
+ reset_data->rcdev.nr_resets = __fls(data->reset_mask) + 1;
+ reset_data->rcdev.ops = &sunxi_gates_reset_ops;
+ reset_data->rcdev.of_node = node;
+ reset_controller_register(&reset_data->rcdev);
}
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