From patchwork Mon Jul 9 14:57:42 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [2/4,V5] mfd: workaround: add companion chip in 88pm80x Date: Mon, 09 Jul 2012 04:57:42 -0000 From: Qiao Zhou X-Patchwork-Id: 169873 Message-Id: <1341845864-13779-3-git-send-email-zhouqiao@marvell.com> To: a.zummo@towertech.it, arnd@arndb.de, broonie@opensource.wolfsonmicro.com, sameo@linux.intel.com, rtc-linux@googlegroups.com, linux-arm-kernel@lists.infradead.org, haojian.zhuang@gmail.com, chao.xie@marvell.com, yu.tang@marvell.com, wilbur.wang@marvell.com Cc: Qiao Zhou in hw design, 800 is mainly for pmic control, while 805 for audio. but there are 3 registers which controls class D speaker property, and they are defined in 800 i2c client domain. so 805 codec driver needs to use 800 i2c client to access class D speaker reg for audio path management. so add this workaround for the purpose to let 805 access 800 i2c in some scenario. Signed-off-by: Qiao Zhou --- drivers/mfd/88pm80x.c | 28 ++++++++++++++++++++++++++++ include/linux/mfd/88pm80x.h | 1 + 2 files changed, 29 insertions(+), 0 deletions(-) diff --git a/drivers/mfd/88pm80x.c b/drivers/mfd/88pm80x.c index 90aa18a..77b8655 100644 --- a/drivers/mfd/88pm80x.c +++ b/drivers/mfd/88pm80x.c @@ -18,6 +18,12 @@ #include #include +/* + * workaround: some registers needed by pm805 are defined in pm800, so + * need to use this global variable to maintain the relation between + * pm800 and pm805. would remove it after HW chip fixes the issue. + */ +static struct pm80x_chip *g_pm80x_chip; const struct regmap_config pm80x_regmap_config = { .reg_bits = 8, @@ -61,6 +67,19 @@ int __devinit pm80x_init(struct i2c_client *client, device_init_wakeup(&client->dev, 1); + /* + * workaround: set g_pm80x_chip to the first probed chip. if the + * second chip is probed, just point to the companion to each + * other so that pm805 can access those specific register. would + * remove it after HW chip fixes the issue. + */ + if (!g_pm80x_chip) + g_pm80x_chip = chip; + else { + chip->companion = g_pm80x_chip->client; + g_pm80x_chip->companion = chip->client; + } + return 0; err_chip_id: @@ -75,6 +94,15 @@ int __devexit pm80x_deinit(struct i2c_client *client) { struct pm80x_chip *chip = i2c_get_clientdata(client); + /* + * workaround: clear the dependency between pm800 and pm805. + * would remove it after HW chip fixes the issue. + */ + if (g_pm80x_chip->companion) + g_pm80x_chip->companion = NULL; + else + g_pm80x_chip = NULL; + regmap_exit(chip->regmap); devm_kfree(&client->dev, chip); diff --git a/include/linux/mfd/88pm80x.h b/include/linux/mfd/88pm80x.h index 6c126e9..103f06d 100644 --- a/include/linux/mfd/88pm80x.h +++ b/include/linux/mfd/88pm80x.h @@ -295,6 +295,7 @@ struct pm80x_chip { struct pm80x_subchip *subchip; struct device *dev; struct i2c_client *client; + struct i2c_client *companion; struct regmap *regmap; struct regmap_irq_chip *regmap_irq_chip; struct regmap_irq_chip_data *irq_data;