Skip to main content

Browse the archive

Revision 02fbabd5f4ed182d2c616e49309f5a3efd9ec671 authored by Fabrice Gasnier on 04 March 2020, 08:55:32 UTC, committed by Mark Brown on 04 March 2020, 13:57:28 UTC 
regulator: stm32-vrefbuf: fix a possible overshoot when re-enabling
 
There maybe an overshoot, when disabling, then re-enabling vrefbuf
too quickly. VREFBUF is used by ADC/DAC on some boards. When re-enabling
too quickly, an overshoot on the reference voltage make the conversions
inaccurate for a short period of time.
- Don't put the VREFBUF in HiZ when disabling, to force an active
discharge.
- Enforce a 1ms OFF/ON delay

Fixes: 0cdbf481e927 ("regulator: Add support for stm32-vrefbuf")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Message-Id: <1583312132-20932-1-git-send-email-fabrice.gasnier@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 parent a5b0cda
Raw File
hecubafb.h 
/*
 * hecubafb.h - definitions for the hecuba framebuffer driver
 *
 * Copyright (C) 2008 by Jaya Kumar
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file COPYING in the main directory of this archive for
 * more details.
 *
 */

#ifndef _LINUX_HECUBAFB_H_
#define _LINUX_HECUBAFB_H_

/* Apollo controller specific defines */
#define APOLLO_START_NEW_IMG	0xA0
#define APOLLO_STOP_IMG_DATA	0xA1
#define APOLLO_DISPLAY_IMG	0xA2
#define APOLLO_ERASE_DISPLAY	0xA3
#define APOLLO_INIT_DISPLAY	0xA4

/* Hecuba interface specific defines */
#define HCB_WUP_BIT	0x01
#define HCB_DS_BIT 	0x02
#define HCB_RW_BIT 	0x04
#define HCB_CD_BIT 	0x08
#define HCB_ACK_BIT 	0x80

/* struct used by hecuba. board specific stuff comes from *board */
struct hecubafb_par {
	struct fb_info *info;
	struct hecuba_board *board;
	void (*send_command)(struct hecubafb_par *, unsigned char);
	void (*send_data)(struct hecubafb_par *, unsigned char);
};

/* board specific routines
board drivers can implement wait_for_ack with interrupts if desired. if
wait_for_ack is called with clear=0, then go to sleep and return when ack
goes hi or if wait_for_ack with clear=1, then return when ack goes lo */
struct hecuba_board {
	struct module *owner;
	void (*remove)(struct hecubafb_par *);
	void (*set_ctl)(struct hecubafb_par *, unsigned char, unsigned char);
	void (*set_data)(struct hecubafb_par *, unsigned char);
	void (*wait_for_ack)(struct hecubafb_par *, int);
	int (*init)(struct hecubafb_par *);
};


#endif
back to top