u-boot/drivers/power/twl4030.c
Grazvydas Ignotas 61712bcad4 twl4030: fix potential power supply handling issues
twl4030_pmrecv_vsel_cfg currently first sets up device group (effectively
enabling the supply), and only then sets vsel (selects voltage). This could
lead to wrong voltage for a short time, or even long time if second i2c
write fails.

Fix this by writing vsel first and device group after that. Also
introduce error checking to not enable the supply if we failed to set
the voltage, and start logging errors as power supply problems are
usually important.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
2012-03-27 22:05:29 +02:00

115 lines
3.3 KiB
C

/*
* Copyright (c) 2009 Wind River Systems, Inc.
* Tom Rix <Tom.Rix at windriver.com>
*
* 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
*
* twl4030_power_reset_init is derived from code on omapzoom,
* git://git.omapzoom.com/repo/u-boot.git
*
* Copyright (C) 2007-2009 Texas Instruments, Inc.
*
* twl4030_power_init is from cpu/omap3/common.c, power_init_r
*
* (C) Copyright 2004-2008
* Texas Instruments, <www.ti.com>
*
* Author :
* Sunil Kumar <sunilsaini05 at gmail.com>
* Shashi Ranjan <shashiranjanmca05 at gmail.com>
*
* Derived from Beagle Board and 3430 SDP code by
* Richard Woodruff <r-woodruff2 at ti.com>
* Syed Mohammed Khasim <khasim at ti.com>
*
*/
#include <twl4030.h>
/*
* Power Reset
*/
void twl4030_power_reset_init(void)
{
u8 val = 0;
if (twl4030_i2c_read_u8(TWL4030_CHIP_PM_MASTER, &val,
TWL4030_PM_MASTER_P1_SW_EVENTS)) {
printf("Error:TWL4030: failed to read the power register\n");
printf("Could not initialize hardware reset\n");
} else {
val |= TWL4030_PM_MASTER_SW_EVENTS_STOPON_PWRON;
if (twl4030_i2c_write_u8(TWL4030_CHIP_PM_MASTER, val,
TWL4030_PM_MASTER_P1_SW_EVENTS)) {
printf("Error:TWL4030: failed to write the power register\n");
printf("Could not initialize hardware reset\n");
}
}
}
/*
* Set Device Group and Voltage
*/
void twl4030_pmrecv_vsel_cfg(u8 vsel_reg, u8 vsel_val,
u8 dev_grp, u8 dev_grp_sel)
{
int ret;
/* Select the Voltage */
ret = twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER, vsel_val,
vsel_reg);
if (ret != 0) {
printf("Could could not write vsel to reg %02x (%d)\n",
vsel_reg, ret);
return;
}
/* Select the Device Group (enable the supply if dev_grp_sel != 0) */
ret = twl4030_i2c_write_u8(TWL4030_CHIP_PM_RECEIVER, dev_grp_sel,
dev_grp);
if (ret != 0)
printf("Could could not write grp_sel to reg %02x (%d)\n",
dev_grp, ret);
}
void twl4030_power_init(void)
{
/* set VAUX3 to 2.8V */
twl4030_pmrecv_vsel_cfg(TWL4030_PM_RECEIVER_VAUX3_DEDICATED,
TWL4030_PM_RECEIVER_VAUX3_VSEL_28,
TWL4030_PM_RECEIVER_VAUX3_DEV_GRP,
TWL4030_PM_RECEIVER_DEV_GRP_P1);
/* set VPLL2 to 1.8V */
twl4030_pmrecv_vsel_cfg(TWL4030_PM_RECEIVER_VPLL2_DEDICATED,
TWL4030_PM_RECEIVER_VPLL2_VSEL_18,
TWL4030_PM_RECEIVER_VPLL2_DEV_GRP,
TWL4030_PM_RECEIVER_DEV_GRP_ALL);
/* set VDAC to 1.8V */
twl4030_pmrecv_vsel_cfg(TWL4030_PM_RECEIVER_VDAC_DEDICATED,
TWL4030_PM_RECEIVER_VDAC_VSEL_18,
TWL4030_PM_RECEIVER_VDAC_DEV_GRP,
TWL4030_PM_RECEIVER_DEV_GRP_P1);
}
void twl4030_power_mmc_init(void)
{
/* Set VMMC1 to 3.15 Volts */
twl4030_pmrecv_vsel_cfg(TWL4030_PM_RECEIVER_VMMC1_DEDICATED,
TWL4030_PM_RECEIVER_VMMC1_VSEL_32,
TWL4030_PM_RECEIVER_VMMC1_DEV_GRP,
TWL4030_PM_RECEIVER_DEV_GRP_P1);
}