linux/drivers/clk/sunxi/clk-sun6i-ar100.c
Lee Jones dcc354572d
clk: sunxi: Demote non-conformant kernel-doc headers
Headers must describe their parameters.

Fixes the following W=1 kernel build warning(s):

 drivers/clk/sunxi/clk-sun9i-core.c:27: warning: Function parameter or member 'req' not described in 'sun9i_a80_get_pll4_factors'
 drivers/clk/sunxi/clk-sun9i-core.c💯 warning: Function parameter or member 'req' not described in 'sun9i_a80_get_gt_factors'
 drivers/clk/sunxi/clk-sun9i-core.c:155: warning: Function parameter or member 'req' not described in 'sun9i_a80_get_ahb_factors'
 drivers/clk/sunxi/clk-sun9i-core.c:235: warning: Function parameter or member 'req' not described in 'sun9i_a80_get_apb1_factors'
 drivers/clk/sunxi/clk-usb.c:22: warning: cannot understand function prototype: 'struct usb_reset_data '
 drivers/clk/sunxi/clk-sun6i-ar100.c:26: warning: Function parameter or member 'req' not described in 'sun6i_get_ar100_factors'

Cc: "Emilio López" <emilio@elopez.com.ar>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@siol.net>
Cc: Boris BREZILLON <boris.brezillon@free-electrons.com>
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20210303142430.3168703-1-lee.jones@linaro.org
2021-03-08 16:47:55 +01:00

107 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2014 Free Electrons
*
* Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
*
* Allwinner A31 AR100 clock driver
*/
#include <linux/bitops.h>
#include <linux/clk-provider.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include "clk-factors.h"
/*
* sun6i_get_ar100_factors - Calculates factors p, m for AR100
*
* AR100 rate is calculated as follows
* rate = (parent_rate >> p) / (m + 1);
*/
static void sun6i_get_ar100_factors(struct factors_request *req)
{
unsigned long div;
int shift;
/* clock only divides */
if (req->rate > req->parent_rate)
req->rate = req->parent_rate;
div = DIV_ROUND_UP(req->parent_rate, req->rate);
if (div < 32)
shift = 0;
else if (div >> 1 < 32)
shift = 1;
else if (div >> 2 < 32)
shift = 2;
else
shift = 3;
div >>= shift;
if (div > 32)
div = 32;
req->rate = (req->parent_rate >> shift) / div;
req->m = div - 1;
req->p = shift;
}
static const struct clk_factors_config sun6i_ar100_config = {
.mwidth = 5,
.mshift = 8,
.pwidth = 2,
.pshift = 4,
};
static const struct factors_data sun6i_ar100_data = {
.mux = 16,
.muxmask = GENMASK(1, 0),
.table = &sun6i_ar100_config,
.getter = sun6i_get_ar100_factors,
};
static DEFINE_SPINLOCK(sun6i_ar100_lock);
static int sun6i_a31_ar100_clk_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct resource *r;
void __iomem *reg;
struct clk *clk;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reg = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(reg))
return PTR_ERR(reg);
clk = sunxi_factors_register(np, &sun6i_ar100_data, &sun6i_ar100_lock,
reg);
if (!clk)
return -ENOMEM;
platform_set_drvdata(pdev, clk);
return 0;
}
static const struct of_device_id sun6i_a31_ar100_clk_dt_ids[] = {
{ .compatible = "allwinner,sun6i-a31-ar100-clk" },
{ /* sentinel */ }
};
static struct platform_driver sun6i_a31_ar100_clk_driver = {
.driver = {
.name = "sun6i-a31-ar100-clk",
.of_match_table = sun6i_a31_ar100_clk_dt_ids,
.suppress_bind_attrs = true,
},
.probe = sun6i_a31_ar100_clk_probe,
};
builtin_platform_driver(sun6i_a31_ar100_clk_driver);