| /* |
| * Tegra pulse width frequency modulator definitions |
| * |
| * Copyright (c) 2011 The Chromium OS Authors. |
| * See file CREDITS for list of people who contributed to this |
| * project. |
| * |
| * 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 |
| */ |
| |
| #ifndef __ASM_ARCH_TEGRA_PWM_H |
| #define __ASM_ARCH_TEGRA_PWM_H |
| |
| /* This is a single PWM channel */ |
| struct pwm_ctlr { |
| uint control; /* Control register */ |
| uint reserved[3]; /* Space space */ |
| }; |
| |
| #define PWM_NUM_CHANNELS 4 |
| |
| /* PWM_CONTROLLER_PWM_CSR_0/1/2/3_0 */ |
| #define PWM_ENABLE_SHIFT 31 |
| #define PWM_ENABLE_MASK (0x1 << PWM_ENABLE_SHIFT) |
| |
| #define PWM_WIDTH_SHIFT 16 |
| #define PWM_WIDTH_MASK (0x7FFF << PWM_WIDTH_SHIFT) |
| |
| #define PWM_DIVIDER_SHIFT 0 |
| #define PWM_DIVIDER_MASK (0x1FFF << PWM_DIVIDER_SHIFT) |
| |
| /** |
| * Program the PWM with the given parameters. |
| * |
| * @param channel PWM channel to update |
| * @param rate Clock rate to use for PWM |
| * @param pulse_width high pulse width: 0=always low, 1=1/256 pulse high, |
| * n = n/256 pulse high |
| * @param freq_divider frequency divider value (1 to use rate as is) |
| */ |
| void pwm_enable(unsigned channel, int rate, int pulse_width, int freq_divider); |
| |
| /** |
| * Request a pwm channel as referenced by a device tree node. |
| * |
| * This channel can then be passed to pwm_enable(). |
| * |
| * @param blob Device tree blob |
| * @param node Node containing reference to pwm |
| * @param prop_name Property name of pwm reference |
| * @return channel number, if ok, else -1 |
| */ |
| int pwm_request(const void *blob, int node, const char *prop_name); |
| |
| /** |
| * Set up the pwm controller, by looking it up in the fdt. |
| * |
| * @return 0 if ok, -1 if the device tree node was not found or invalid. |
| */ |
| int pwm_init(const void *blob); |
| |
| #endif /* __ASM_ARCH_TEGRA_PWM_H */ |
