From mboxrd@z Thu Jan 1 00:00:00 1970 From: Billy Laws Subject: Re: [2/2] mfd: max77620: Add low battery monitor support Date: Tue, 29 Jan 2019 13:33:46 +0000 Message-ID: References: <3587c682-e1db-5140-fd8e-13c46d882dd3@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Mark Zhang Cc: Lee Jones , linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org, Laxman Dewangan , Venkat Reddy Talla List-Id: linux-tegra@vger.kernel.org It does, see this article https://blog.quendi.moe/2018/07/03/en-debugging-nintendo-switch-linux-power-management-battery-desync-edition/ On Tue, Jan 29, 2019 at 9:03 AM Mark Zhang wrote: > > On 1/29/2019 3:36 PM, Billy Laws wrote: > > Sure, that's fine with me, will send then this gets accepted. Two > > other things: you should probably set the reg to 0 if the property > > isn't specified as regmap_add_irqchip sets it to 0xff (basically all > > enabled on highest limit), and you haven't updated the dt-bindings. > > Billy, v2 is out, dt-bindings patches are added. > But after a second thought, I don't think regmap_add_irqchip might set > registers to 0xff. I mean, for 2 registers which this patch set touches, > they're not IRQ registers(mask/status/...), so regmap_add_irqchip should > not touch them so I didn't make changes to driver codes in v2. > > Mark > > > > > On Tue, Jan 29, 2019 at 6:52 AM Mark Zhang wrote: > >> > >> On 1/27/2019 10:54 PM, Billy Laws wrote: > >>> >This patch adds PMIC configurations for low-battery > >>> >monitoring by handling max77620 register CNFGGLBL1. > >>> > > >>> It might be an idea to add lbhyst configuration here and support using > >>> custom lbdac values to specify a different cutoff point. > >> > >> Yeah this patch doesn't have support to program LBHYST & LBDAC because > >> according to our experiences, we don't have requirement to modify them > >> when low battery monitor support added. > >> > >> I think we can create a new patch to support these 2 fields in the future > >> when we really need them. Or you can create a patch if you have requirement > >> for them, is this OK to you Billy? > >> > >> Mark > >> > >>> > >>> See: https://datasheetspdf.com/pdf-file/924230/Maxim/MAX8698C/1 pg 46 > >>> >Signed-off-by: Laxman Dewangan > >>> >Signed-off-by: Venkat Reddy Talla > >>> >Signed-off-by: Mark Zhang > >>> >--- > >>> > drivers/mfd/max77620.c | 57 +++++++++++++++++++++++++++++++++++++++++- > >>> > 1 file changed, 56 insertions(+), 1 deletion(-) > >>> > > >>> >diff --git a/drivers/mfd/max77620.c b/drivers/mfd/max77620.c > >>> >index f58143103185..9e50d145afd8 100644 > >>> >--- a/drivers/mfd/max77620.c > >>> >+++ b/drivers/mfd/max77620.c > >>> >@@ -474,6 +474,57 @@ static int > >>> max77620_init_backup_battery_charging(struct max77620_chip *chip) > >>> > return ret; > >>> > } > >>> > > >>> >+static int max77620_init_low_battery_monitor(struct max77620_chip *chip) > >>> >+{ > >>> >+ struct device *dev = chip->dev; > >>> >+ struct device_node *np; > >>> >+ bool pval; > >>> >+ u8 mask = 0; > >>> >+ u8 val = 0; > >>> >+ int ret; > >>> >+ > >>> >+ np = of_get_child_by_name(dev->of_node, "low-battery-monitor"); > >>> >+ if (!np) { > >>> >+ dev_info(dev, "Low battery monitoring support disabled\n"); > >>> >+ return 0; > >>> >+ } > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-dac-enable"); > >>> >+ if (pval) { > >>> >+ mask |= MAX77620_CNFGGLBL1_LBDAC_EN; > >>> >+ val |= MAX77620_CNFGGLBL1_LBDAC_EN; > >>> >+ } > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-dac-disable"); > >>> >+ if (pval) > >>> >+ mask |= MAX77620_CNFGGLBL1_LBDAC_EN; > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-shutdown-enable"); > >>> >+ if (pval) { > >>> >+ mask |= MAX77620_CNFGGLBL1_MPPLD; > >>> >+ val |= MAX77620_CNFGGLBL1_MPPLD; > >>> >+ } > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-shutdown-disable"); > >>> >+ if (pval) > >>> >+ mask |= MAX77620_CNFGGLBL1_MPPLD; > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-reset-enable"); > >>> >+ if (pval) { > >>> >+ mask |= MAX77620_CNFGGLBL1_LBRSTEN; > >>> >+ val |= MAX77620_CNFGGLBL1_LBRSTEN; > >>> >+ } > >>> >+ > >>> >+ pval = of_property_read_bool(np, "maxim,low-battery-reset-disable"); > >>> >+ if (pval) > >>> >+ mask |= MAX77620_CNFGGLBL1_LBRSTEN; > >>> >+ > >>> >+ ret = regmap_update_bits(chip->rmap, MAX77620_REG_CNFGGLBL1, mask, val); > >>> >+ if (ret < 0) > >>> >+ dev_err(dev, "Reg CNFGGLBL1 update failed: %d\n", ret); > >>> >+ return ret; > >>> >+} > >>> >+ > >>> > static int max77620_read_es_version(struct max77620_chip *chip) > >>> > { > >>> > unsigned int val; > >>> >@@ -563,7 +614,11 @@ static int max77620_probe(struct i2c_client *client, > >>> > if (ret < 0) > >>> > return ret; > >>> > > >>> >- ret = devm_mfd_add_devices(chip->dev, PLATFORM_DEVID_NONE, > >>> >+ ret = max77620_init_low_battery_monitor(chip); > >>> >+ if (ret < 0) > >>> >+ return ret; > >>> >+ > >>> >+ ret = devm_mfd_add_devices(chip->dev, PLATFORM_DEVID_NONE, > >>> > mfd_cells, n_mfd_cells, NULL, 0, > >>> > regmap_irq_get_domain(chip->top_irq_data)); > >>> > if (ret < 0) { > >>>