File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c
new file mode 100644
index 0000000..a634b11
--- /dev/null
+++ b/drivers/clk/imx/clk.c
@@ -0,0 +1,113 @@
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include "clk.h"
+
+DEFINE_SPINLOCK(imx_ccm_lock);
+
+void __init imx_check_clocks(struct clk *clks[], unsigned int count)
+{
+ unsigned i;
+
+ for (i = 0; i < count; i++)
+ if (IS_ERR(clks[i]))
+ pr_err("i.MX clk %u: register failed with %ld\n",
+ i, PTR_ERR(clks[i]));
+}
+
+static struct clk * __init imx_obtain_fixed_clock_from_dt(const char *name)
+{
+ struct of_phandle_args phandle;
+ struct clk *clk = ERR_PTR(-ENODEV);
+ char *path;
+
+ path = kasprintf(GFP_KERNEL, "/clocks/%s", name);
+ if (!path)
+ return ERR_PTR(-ENOMEM);
+
+ phandle.np = of_find_node_by_path(path);
+ kfree(path);
+
+ if (phandle.np) {
+ clk = of_clk_get_from_provider(&phandle);
+ of_node_put(phandle.np);
+ }
+ return clk;
+}
+
+struct clk * __init imx_obtain_fixed_clock(
+ const char *name, unsigned long rate)
+{
+ struct clk *clk;
+
+ clk = imx_obtain_fixed_clock_from_dt(name);
+ if (IS_ERR(clk))
+ clk = imx_clk_fixed(name, rate);
+ return clk;
+}
+
+/*
+ * This fixups the register CCM_CSCMR1 write value.
+ * The write/read/divider values of the aclk_podf field
+ * of that register have the relationship described by
+ * the following table:
+ *
+ * write value read value divider
+ * 3b'000 3b'110 7
+ * 3b'001 3b'111 8
+ * 3b'010 3b'100 5
+ * 3b'011 3b'101 6
+ * 3b'100 3b'010 3
+ * 3b'101 3b'011 4
+ * 3b'110 3b'000 1
+ * 3b'111 3b'001 2(default)
+ *
+ * That's why we do the xor operation below.
+ */
+#define CSCMR1_FIXUP 0x00600000
+
+void imx_cscmr1_fixup(u32 *val)
+{
+ *val ^= CSCMR1_FIXUP;
+ return;
+}
+
+static int imx_keep_uart_clocks __initdata;
+static struct clk ** const *imx_uart_clocks __initdata;
+
+static int __init imx_keep_uart_clocks_param(char *str)
+{
+ imx_keep_uart_clocks = 1;
+
+ return 0;
+}
+__setup_param("earlycon", imx_keep_uart_earlycon,
+ imx_keep_uart_clocks_param, 0);
+__setup_param("earlyprintk", imx_keep_uart_earlyprintk,
+ imx_keep_uart_clocks_param, 0);
+
+void __init imx_register_uart_clocks(struct clk ** const clks[])
+{
+ if (imx_keep_uart_clocks) {
+ int i;
+
+ imx_uart_clocks = clks;
+ for (i = 0; imx_uart_clocks[i]; i++)
+ clk_prepare_enable(*imx_uart_clocks[i]);
+ }
+}
+
+static int __init imx_clk_disable_uart(void)
+{
+ if (imx_keep_uart_clocks && imx_uart_clocks) {
+ int i;
+
+ for (i = 0; imx_uart_clocks[i]; i++)
+ clk_disable_unprepare(*imx_uart_clocks[i]);
+ }
+
+ return 0;
+}
+late_initcall_sync(imx_clk_disable_uart);