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Date: Fri, 22 Apr 2022 08:16:31 +0200 From: Helmut Grohne <helmut.grohne@...enta.de> To: Support Opensource <support.opensource@...semi.com>, Lee Jones <lee.jones@...aro.org> CC: <linux-kernel@...r.kernel.org>, Adam Thomson <Adam.Thomson.Opensource@...semi.com>, Mark Brown <broonie@...nel.org>, Wolfram Sang <wsa@...-dreams.de> Subject: [PATCH v2 1/2] mfd: da9062: enable being a system-power-controller The DA9062 can be the device used to power the CPU. In that case, it can be used to power off the system. In the CONTROL_A register, the M_*_EN bits must be zero for the corresponding *_EN bits to have an effect. We zero them all to turn off the system. Signed-off-by: Helmut Grohne <helmut.grohne@...enta.de> --- drivers/mfd/da9062-core.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) This series effectively is a rebased resend. The earlier posting was https://lore.kernel.org/all/20200107120559.GA700@laureti-dev/. At that time, Adam Thomson critisized the use of regmap and i2c inside a pm_power_off hook since irqs are disabled. He reached out to Lee Jones, who asked Mark Brown and Wolfram Sang, but never got any reply. I noted that a fair number of other drivers do use regmap and i2c despite this issue. In the mean time, more instances were added: * drivers/mfd/acer-ec-a500.c uses i2c * drivers/mfd/ntxec.c uses i2c * drivers/mfd/rk808.c uses regmap and i2c Given that we proceeded with accepting the use of i2c and regmap inside pm_power_off hooks, I think we can proceed with this patch as well. Helmut diff --git a/drivers/mfd/da9062-core.c b/drivers/mfd/da9062-core.c index 2774b2cbaea6..e7af5b5f16e0 100644 --- a/drivers/mfd/da9062-core.c +++ b/drivers/mfd/da9062-core.c @@ -620,6 +620,23 @@ static const struct of_device_id da9062_dt_ids[] = { }; MODULE_DEVICE_TABLE(of, da9062_dt_ids); +/* Hold client since pm_power_off is global. */ +static struct i2c_client *da9062_i2c_client; + +static void da9062_power_off(void) +{ + struct da9062 *chip = i2c_get_clientdata(da9062_i2c_client); + const unsigned int mask = DA9062AA_SYSTEM_EN_MASK | + DA9062AA_POWER_EN_MASK | DA9062AA_POWER1_EN_MASK | + DA9062AA_M_SYSTEM_EN_MASK | DA9062AA_M_POWER_EN_MASK | + DA9062AA_M_POWER1_EN_MASK; + int ret = regmap_update_bits(chip->regmap, DA9062AA_CONTROL_A, mask, 0); + + if (ret < 0) + dev_err(&da9062_i2c_client->dev, + "DA9062AA_CONTROL_A update failed, %d\n", ret); +} + static int da9062_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) { @@ -720,6 +737,15 @@ static int da9062_i2c_probe(struct i2c_client *i2c, return ret; } + if (of_device_is_system_power_controller(i2c->dev.of_node)) { + if (!pm_power_off) { + da9062_i2c_client = i2c; + pm_power_off = da9062_power_off; + } else { + dev_warn(&i2c->dev, "Poweroff callback already assigned\n"); + } + } + return ret; } @@ -727,6 +753,11 @@ static int da9062_i2c_remove(struct i2c_client *i2c) { struct da9062 *chip = i2c_get_clientdata(i2c); + if (pm_power_off == da9062_power_off) + pm_power_off = NULL; + if (da9062_i2c_client) + da9062_i2c_client = NULL; + mfd_remove_devices(chip->dev); regmap_del_irq_chip(i2c->irq, chip->regmap_irq); -- 2.20.1 Dipl.-Inf. Helmut Grohne Research and Development Application Engineering Phone: +49 (371) 24354 0 ∙ Fax: +49 (371) 24354 020 helmut.grohne@...enta.de ∙ https://www.intenta.de Intenta GmbH ∙ Ahornstraße 55 ∙ 09112 Chemnitz, Germany Managing Director: Dr.-Ing. Basel Fardi ∙ VAT/USt-IdNr.: DE 275745394 Commercial register: HRB 26404 Amtsgericht Chemnitz
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