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/*
* Porting to u-boot:
* Linux IMX PWM driver
*
* Copyright (C) 2011 Freescale Semiconductor, Inc.
*
* 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/types.h>
#include <asm/io.h>
#include <asm/imx_pwm.h>
#include <common.h>
#include <div64.h>
#define MX_PWMCR 0x00 /* PWM Control Register */
#define MX_PWMSAR 0x0C /* PWM Sample Register */
#define MX_PWMPR 0x10 /* PWM Period Register */
#define MX_PWMCR_PRESCALER(x) (((x - 1) & 0xFFF) << 4)
#define MX_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
#define MX_PWMCR_CLKSRC_IPG (1 << 16)
#define MX_PWMCR_EN (1 << 0)
#define MX_PWMCR_STOPEN (1 << 25)
#define MX_PWMCR_DOZEEN (1 << 24)
#define MX_PWMCR_WAITEN (1 << 23)
#define MX_PWMCR_DBGEN (1 << 22)
#define MX_PWMCR_CLKSRC_IPG (1 << 16)
#define MX_PWMCR_CLKSRC_IPG_32k (3 << 16)
int imx_pwm_config(struct pwm_device pwm, int duty_ns, int period_ns)
{
unsigned long long c;
unsigned long period_cycles, duty_cycles, prescale;
u32 cr;
if (period_ns == 0 || duty_ns > period_ns)
return -1;
pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE:
(unsigned long)IMX_PWM1_BASE;
if (pwm.pwmo_invert)
duty_ns = period_ns - duty_ns;
c = mxc_get_clock(MXC_IPG_PERCLK);
c = c * period_ns;
do_div(c, 1000000000);
period_cycles = c;
prescale = period_cycles / 0x10000 + 1;
period_cycles /= prescale;
c = (unsigned long long)period_cycles * duty_ns;
do_div(c, period_ns);
duty_cycles = c;
writel(duty_cycles, pwm.mmio_base + MX_PWMSAR);
writel(period_cycles, pwm.mmio_base + MX_PWMPR);
cr = MX_PWMCR_PRESCALER(prescale) |
MX_PWMCR_STOPEN | MX_PWMCR_DOZEEN |
MX_PWMCR_WAITEN | MX_PWMCR_DBGEN;
cr |= MX_PWMCR_CLKSRC_IPG_HIGH;
writel(cr, pwm.mmio_base + MX_PWMCR);
return 0;
}
int imx_pwm_enable(struct pwm_device pwm)
{
unsigned long reg;
int rc = 0;
if (pwm.enable_pwm_clk)
pwm.enable_pwm_clk();
pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE:
(unsigned long)IMX_PWM1_BASE;
reg = readl(pwm.mmio_base + MX_PWMCR);
reg |= MX_PWMCR_EN;
writel(reg, pwm.mmio_base + MX_PWMCR);
if (pwm.enable_pwm_pad)
pwm.enable_pwm_pad();
return rc;
}
int imx_pwm_disable(struct pwm_device pwm)
{
if (pwm.disable_pwm_pad)
pwm.disable_pwm_pad();
pwm.mmio_base = pwm.pwm_id ? (unsigned long)IMX_PWM2_BASE:
(unsigned long)IMX_PWM1_BASE;
writel(0, pwm.mmio_base + MX_PWMCR);
if (pwm.disable_pwm_clk)
pwm.disable_pwm_clk();
return 0;
}
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