platform: msm: Add qpnp-pwm driver
Add the qpnp-pwm driver to support LPG/PWM devices in Qualcomm
plug-and-play (QPNP) PMIC chips. QPNP chips make use of
Qualcomm's SPMI register convention. LPG module provides a superset
of functionality provided by PWM device such as user defined pattern
generation, driving multiple PWM channels etc.
Change-Id: I29a22c6e655612d93cac10e6eea76383d37775e2
Signed-off-by: Jay Chokshi <jchokshi@codeaurora.org>
diff --git a/include/linux/qpnp/pwm.h b/include/linux/qpnp/pwm.h
new file mode 100644
index 0000000..de89a37
--- /dev/null
+++ b/include/linux/qpnp/pwm.h
@@ -0,0 +1,168 @@
+/* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#ifndef __QPNP_PWM_H__
+#define __QPNP_PWM_H__
+
+#include <linux/pwm.h>
+
+/* usec: 19.2M, n=6, m=0, pre=2 */
+#define PM_PWM_PERIOD_MIN 7
+/* 1K, n=9, m=7, pre=6 */
+#define PM_PWM_PERIOD_MAX (384 * USEC_PER_SEC)
+#define PM_PWM_LUT_RAMP_STEP_TIME_MAX 499
+#define PM_PWM_MAX_PAUSE_CNT 8191
+/*
+ * Formula from HSID,
+ * pause_time (hi/lo) = (pause_code - 1)*(duty_ms)
+ */
+#define PM_PWM_LUT_PAUSE_MAX \
+ ((PM_PWM_MAX_PAUSE_CNT - 1) * PM_PWM_LUT_RAMP_STEP_TIME_MAX) /* ms */
+
+/* Flags for Look Up Table */
+#define PM_PWM_LUT_LOOP 0x01
+#define PM_PWM_LUT_RAMP_UP 0x02
+#define PM_PWM_LUT_REVERSE 0x04
+#define PM_PWM_LUT_PAUSE_HI_EN 0x08
+#define PM_PWM_LUT_PAUSE_LO_EN 0x10
+
+#define PM_PWM_LUT_NO_TABLE 0x20
+#define PM_PWM_LUT_USE_RAW_VALUE 0x40
+
+/*
+ * PWM frequency/period control
+ *
+ * PWM Frequency = ClockFrequency / (N * T)
+ * or
+ * PWM Period = Clock Period * (N * T)
+ * where
+ * N = 2^9 or 2^6 for 9-bit or 6-bit PWM size
+ * T = Pre-divide * 2^m, m = 0..7 (exponent)
+ */
+
+/*
+ * enum pm_pwm_size - PWM bit mode selection
+ * %PM_PWM_SIZE_6BIT - Select 6 bit mode; 64 levels
+ * %PM_PWM_SIZE_9BIT - Select 9 bit mode; 512 levels
+ */
+enum pm_pwm_size {
+ PM_PWM_SIZE_6BIT = 6,
+ PM_PWM_SIZE_9BIT = 9,
+};
+
+/*
+ * enum pm_pwm_clk - PWM clock selection
+ * %PM_PWM_CLK_1KHZ - 1KHz clock
+ * %PM_PWM_CLK_32KHZ - 32KHz clock
+ * %PM_PWM_CLK_19P2MHZ - 19.2MHz clock
+ * Note: Here 1KHz = 1024Hz
+ */
+enum pm_pwm_clk {
+ PM_PWM_CLK_1KHZ,
+ PM_PWM_CLK_32KHZ,
+ PM_PWM_CLK_19P2MHZ,
+};
+
+/* PWM pre-divider selection */
+enum pm_pwm_pre_div {
+ PM_PWM_PDIV_2,
+ PM_PWM_PDIV_3,
+ PM_PWM_PDIV_5,
+ PM_PWM_PDIV_6,
+};
+
+/*
+ * struct pwm_period_config - PWM period configuration
+ * @pwm_size: enum pm_pwm_size
+ * @clk: enum pm_pwm_clk
+ * @pre_div: enum pm_pwm_pre_div
+ * @pre_div_exp: exponent of 2 as part of pre-divider: 0..7
+ */
+struct pwm_period_config {
+ enum pm_pwm_size pwm_size;
+ enum pm_pwm_clk clk;
+ enum pm_pwm_pre_div pre_div;
+ int pre_div_exp;
+};
+
+/*
+ * struct pwm_duty_cycles - PWM duty cycle info
+ * duty_pcts - pointer to an array of duty percentage for a pwm period
+ * num_duty_pcts - total entries in duty_pcts array
+ * duty_ms - duty cycle time in ms
+ * start_idx - index in the LUT
+ */
+struct pwm_duty_cycles {
+ int *duty_pcts;
+ int num_duty_pcts;
+ int duty_ms;
+ int start_idx;
+};
+
+int pwm_config_period(struct pwm_device *pwm,
+ struct pwm_period_config *pwm_p);
+
+int pwm_config_pwm_value(struct pwm_device *pwm, int pwm_value);
+
+/*
+ * lut_params: Lookup table (LUT) parameters
+ * @start_idx: start index in lookup table from 0 to MAX-1
+ * @idx_len: number of index
+ * @pause_lo: pause time in millisecond at low index
+ * @pause_hi: pause time in millisecond at high index
+ * @ramp_step_ms: time before loading next LUT pattern in millisecond
+ * @flags: control flags
+ */
+struct lut_params {
+ int start_idx;
+ int idx_len;
+ int lut_pause_hi;
+ int lut_pause_lo;
+ int ramp_step_ms;
+ int flags;
+};
+
+int pwm_lut_config(struct pwm_device *pwm, int period_us,
+ int duty_pct[], struct lut_params lut_params);
+
+int pwm_lut_enable(struct pwm_device *pwm, int start);
+
+/* Standard APIs supported */
+/*
+ * pwm_request - request a PWM device
+ * @pwm_id: PWM id or channel
+ * @label: the label to identify the user
+ */
+
+/*
+ * pwm_free - free a PWM device
+ * @pwm: the PWM device
+ */
+
+/*
+ * pwm_config - change a PWM device configuration
+ * @pwm: the PWM device
+ * @period_us: period in microsecond
+ * @duty_us: duty cycle in microsecond
+ */
+
+/*
+ * pwm_enable - start a PWM output toggling
+ * @pwm: the PWM device
+ */
+
+/*
+ * pwm_disable - stop a PWM output toggling
+ * @pwm: the PWM device
+ */
+
+#endif /* __QPNP_PWM_H__ */