1 files changed, 159 insertions, 0 deletions

diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c
new file mode 100644
index 000000000000..ae3263bc1476
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,159 @@
+/*
+ *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#include "pmc.h"
+
+#define UTMI_FIXED_MUL          40
+
+struct clk_utmi {
+        struct clk_hw hw;
+        struct at91_pmc *pmc;
+        unsigned int irq;
+        wait_queue_head_t wait;
+};
+
+#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
+
+static irqreturn_t clk_utmi_irq_handler(int irq, void *dev_id)
+{
+        struct clk_utmi *utmi = (struct clk_utmi *)dev_id;
+
+        wake_up(&utmi->wait);
+        disable_irq_nosync(utmi->irq);
+
+        return IRQ_HANDLED;
+}
+
+static int clk_utmi_prepare(struct clk_hw *hw)
+{
+        struct clk_utmi *utmi = to_clk_utmi(hw);
+        struct at91_pmc *pmc = utmi->pmc;
+        u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) | AT91_PMC_UPLLEN |
+                  AT91_PMC_UPLLCOUNT | AT91_PMC_BIASEN;
+
+        pmc_write(pmc, AT91_CKGR_UCKR, tmp);
+
+        while (!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU)) {
+                enable_irq(utmi->irq);
+                wait_event(utmi->wait,
+                           pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU);
+        }
+
+        return 0;
+}
+
+static int clk_utmi_is_prepared(struct clk_hw *hw)
+{
+        struct clk_utmi *utmi = to_clk_utmi(hw);
+        struct at91_pmc *pmc = utmi->pmc;
+
+        return !!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU);
+}
+
+static void clk_utmi_unprepare(struct clk_hw *hw)
+{
+        struct clk_utmi *utmi = to_clk_utmi(hw);
+        struct at91_pmc *pmc = utmi->pmc;
+        u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) & ~AT91_PMC_UPLLEN;
+
+        pmc_write(pmc, AT91_CKGR_UCKR, tmp);
+}
+
+static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
+                                          unsigned long parent_rate)
+{
+        /* UTMI clk is a fixed clk multiplier */
+        return parent_rate * UTMI_FIXED_MUL;
+}
+
+static const struct clk_ops utmi_ops = {
+        .prepare = clk_utmi_prepare,
+        .unprepare = clk_utmi_unprepare,
+        .is_prepared = clk_utmi_is_prepared,
+        .recalc_rate = clk_utmi_recalc_rate,
+};
+
+static struct clk * __init
+at91_clk_register_utmi(struct at91_pmc *pmc, unsigned int irq,
+                       const char *name, const char *parent_name)
+{
+        int ret;
+        struct clk_utmi *utmi;
+        struct clk *clk = NULL;
+        struct clk_init_data init;
+
+        utmi = kzalloc(sizeof(*utmi), GFP_KERNEL);
+        if (!utmi)
+                return ERR_PTR(-ENOMEM);
+
+        init.name = name;
+        init.ops = &utmi_ops;
+        init.parent_names = parent_name ? &parent_name : NULL;
+        init.num_parents = parent_name ? 1 : 0;
+        init.flags = CLK_SET_RATE_GATE;
+
+        utmi->hw.init = &init;
+        utmi->pmc = pmc;
+        utmi->irq = irq;
+        init_waitqueue_head(&utmi->wait);
+        irq_set_status_flags(utmi->irq, IRQ_NOAUTOEN);
+        ret = request_irq(utmi->irq, clk_utmi_irq_handler,
+                          IRQF_TRIGGER_HIGH, "clk-utmi", utmi);
+        if (ret)
+                return ERR_PTR(ret);
+
+        clk = clk_register(NULL, &utmi->hw);
+        if (IS_ERR(clk))
+                kfree(utmi);
+
+        return clk;
+}
+
+static void __init
+of_at91_clk_utmi_setup(struct device_node *np, struct at91_pmc *pmc)
+{
+        unsigned int irq;
+        struct clk *clk;
+        const char *parent_name;
+        const char *name = np->name;
+
+        parent_name = of_clk_get_parent_name(np, 0);
+
+        of_property_read_string(np, "clock-output-names", &name);
+
+        irq = irq_of_parse_and_map(np, 0);
+        if (!irq)
+                return;
+
+        clk = at91_clk_register_utmi(pmc, irq, name, parent_name);
+        if (IS_ERR(clk))
+                return;
+
+        of_clk_add_provider(np, of_clk_src_simple_get, clk);
+        return;
+}
+
+void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np,
+                                         struct at91_pmc *pmc)
+{
+        of_at91_clk_utmi_setup(np, pmc);
+}