linux/drivers/clk/clk-bcm2835.c
Simon Arlott 75fabc3f64 ARM: bcm2835: add stub clock driver
This patch adds a minimal stub clock driver for the BCM2835. Its sole
purpose is to allow the PL011 AMBA clk_get() API calls to provide
something that looks enough like a clock that the driver probes and
operates correctly.

This patch was extracted from git://github.com/lp0/linux.git branch
rpi-split as of 2012/09/08, and modified as follows:

* Reworked to call clk_register_fixed_rate(), and clk_register_clkdev()
  rather than using static data to represent the clocks.
* Moved implementation to drivers/clk/.
* Modified .dev_id for UART clocks to match UART DT node names.
* s/bcm2708/bcm2835/.
* Modified device tree vendor prefix.

Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Dom Cobley <popcornmix@gmail.com>
Signed-off-by: Dom Cobley <dc4@broadcom.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Mike Turquette <mturquette@linaro.org>
2012-09-19 19:08:53 -06:00

59 lines
1.9 KiB
C

/*
* Copyright (C) 2010 Broadcom
* Copyright (C) 2012 Stephen Warren
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/bcm2835.h>
/*
* These are fixed clocks. They're probably not all root clocks and it may
* be possible to turn them on and off but until this is mapped out better
* it's the only way they can be used.
*/
void __init bcm2835_init_clocks(void)
{
struct clk *clk;
int ret;
clk = clk_register_fixed_rate(NULL, "sys_pclk", NULL, CLK_IS_ROOT,
250000000);
if (!clk)
pr_err("sys_pclk not registered\n");
clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT,
126000000);
if (!clk)
pr_err("apb_pclk not registered\n");
clk = clk_register_fixed_rate(NULL, "uart0_pclk", NULL, CLK_IS_ROOT,
3000000);
if (!clk)
pr_err("uart0_pclk not registered\n");
ret = clk_register_clkdev(clk, NULL, "20201000.uart");
if (ret)
pr_err("uart0_pclk alias not registered\n");
clk = clk_register_fixed_rate(NULL, "uart1_pclk", NULL, CLK_IS_ROOT,
125000000);
if (!clk)
pr_err("uart1_pclk not registered\n");
ret = clk_register_clkdev(clk, NULL, "20215000.uart");
if (ret)
pr_err("uart0_pclk alias not registered\n");
}