linux_dsm_epyc7002/drivers/clk/ti/clockdomain.c
Sebastian Andrzej Siewior 319f1276f9 clk: ti: consider the fact that of_clk_get() might return an error
I "forgot" to update the dtb and the kernel crashed:
|Unable to handle kernel NULL pointer dereference at virtual address 0000002e
|PC is at __clk_get_flags+0x4/0xc
|LR is at ti_dt_clockdomains_setup+0x70/0xe8

because I did not have the clock nodes. of_clk_get() returns an error
pointer which is not checked here.

Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
2014-09-29 11:51:13 +03:00

76 lines
2.1 KiB
C

/*
* OMAP clockdomain support
*
* Copyright (C) 2013 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; 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/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk/ti.h>
#undef pr_fmt
#define pr_fmt(fmt) "%s: " fmt, __func__
static void __init of_ti_clockdomain_setup(struct device_node *node)
{
struct clk *clk;
struct clk_hw *clk_hw;
const char *clkdm_name = node->name;
int i;
int num_clks;
num_clks = of_count_phandle_with_args(node, "clocks", "#clock-cells");
for (i = 0; i < num_clks; i++) {
clk = of_clk_get(node, i);
if (IS_ERR(clk)) {
pr_err("%s: Failed get %s' clock nr %d (%ld)\n",
__func__, node->full_name, i, PTR_ERR(clk));
continue;
}
if (__clk_get_flags(clk) & CLK_IS_BASIC) {
pr_warn("can't setup clkdm for basic clk %s\n",
__clk_get_name(clk));
continue;
}
clk_hw = __clk_get_hw(clk);
to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name;
omap2_init_clk_clkdm(clk_hw);
}
}
static struct of_device_id ti_clkdm_match_table[] __initdata = {
{ .compatible = "ti,clockdomain" },
{ }
};
/**
* ti_dt_clockdomains_setup - setup device tree clockdomains
*
* Initializes clockdomain nodes for a SoC. This parses through all the
* nodes with compatible = "ti,clockdomain", and add the clockdomain
* info for all the clocks listed under these. This function shall be
* called after rest of the DT clock init has completed and all
* clock nodes have been registered.
*/
void __init ti_dt_clockdomains_setup(void)
{
struct device_node *np;
for_each_matching_node(np, ti_clkdm_match_table) {
of_ti_clockdomain_setup(np);
}
}