7c74c220e9
Before this commit sunxi_factors_register uses of_iomap(node, 0) to get the clk registers. The sun6i prcm has factor clocks, for which we want to use sunxi_factors_register, but of_iomap(node, 0) does not work for the prcm factor clocks, because the prcm uses the mfd framework, so the registers are not part of the dt-node, instead they are added to the platform_device, as platform_device resources. This commit makes getting the registers the callers duty, so that sunxi_factors_register can be used with mfd instantiated platform device too. While at it also add error checking to the of_iomap calls. This commit also drops the __init function from sunxi_factors_register since platform driver probe functions are not __init. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
88 lines
2.1 KiB
C
88 lines
2.1 KiB
C
/*
|
|
* Copyright 2014 Chen-Yu Tsai
|
|
*
|
|
* Chen-Yu Tsai <wens@csie.org>
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/clkdev.h>
|
|
#include <linux/of_address.h>
|
|
|
|
#include "clk-factors.h"
|
|
|
|
/**
|
|
* sun8i_a23_get_mbus_factors() - calculates m factor for MBUS clocks
|
|
* MBUS rate is calculated as follows
|
|
* rate = parent_rate / (m + 1);
|
|
*/
|
|
|
|
static void sun8i_a23_get_mbus_factors(u32 *freq, u32 parent_rate,
|
|
u8 *n, u8 *k, u8 *m, u8 *p)
|
|
{
|
|
u8 div;
|
|
|
|
/*
|
|
* These clocks can only divide, so we will never be able to
|
|
* achieve frequencies higher than the parent frequency
|
|
*/
|
|
if (*freq > parent_rate)
|
|
*freq = parent_rate;
|
|
|
|
div = DIV_ROUND_UP(parent_rate, *freq);
|
|
|
|
if (div > 8)
|
|
div = 8;
|
|
|
|
*freq = parent_rate / div;
|
|
|
|
/* we were called to round the frequency, we can now return */
|
|
if (m == NULL)
|
|
return;
|
|
|
|
*m = div - 1;
|
|
}
|
|
|
|
static struct clk_factors_config sun8i_a23_mbus_config = {
|
|
.mshift = 0,
|
|
.mwidth = 3,
|
|
};
|
|
|
|
static const struct factors_data sun8i_a23_mbus_data __initconst = {
|
|
.enable = 31,
|
|
.mux = 24,
|
|
.muxmask = BIT(1) | BIT(0),
|
|
.table = &sun8i_a23_mbus_config,
|
|
.getter = sun8i_a23_get_mbus_factors,
|
|
};
|
|
|
|
static DEFINE_SPINLOCK(sun8i_a23_mbus_lock);
|
|
|
|
static void __init sun8i_a23_mbus_setup(struct device_node *node)
|
|
{
|
|
struct clk *mbus;
|
|
void __iomem *reg;
|
|
|
|
reg = of_iomap(node, 0);
|
|
if (!reg) {
|
|
pr_err("Could not get registers for a23-mbus-clk\n");
|
|
return;
|
|
}
|
|
|
|
mbus = sunxi_factors_register(node, &sun8i_a23_mbus_data,
|
|
&sun8i_a23_mbus_lock, reg);
|
|
|
|
/* The MBUS clocks needs to be always enabled */
|
|
__clk_get(mbus);
|
|
clk_prepare_enable(mbus);
|
|
}
|
|
CLK_OF_DECLARE(sun8i_a23_mbus, "allwinner,sun8i-a23-mbus-clk", sun8i_a23_mbus_setup);
|