diff options
| -rw-r--r-- | drivers/staging/iio/adc/palmas_gpadc.c | 126 |
1 files changed, 102 insertions, 24 deletions
diff --git a/drivers/staging/iio/adc/palmas_gpadc.c b/drivers/staging/iio/adc/palmas_gpadc.c index 26a94122c505..64bafc077a01 100644 --- a/drivers/staging/iio/adc/palmas_gpadc.c +++ b/drivers/staging/iio/adc/palmas_gpadc.c @@ -111,22 +111,22 @@ struct palmas_gpadc { * mode feature. * Details: * When the AUTO mode is the only conversion mode enabled, if the AUTO - * mode feature is disabled with bit GPADC_AUTO_CTRL. AUTO_CONV1_EN = 0 - * or bit GPADC_AUTO_CTRL. AUTO_CONV0_EN = 0 during a conversion, the + * mode feature is disabled with bit GPADC_AUTO_CTRL.AUTO_CONV1_EN = 0 + * or bit GPADC_AUTO_CTRL.AUTO_CONV0_EN = 0 during a conversion, the * conversion mechanism can be seen as locked meaning that all following - * conversion will give 0 as a result. Bit GPADC_STATUS.GPADC_AVAILABLE - * will stay at 0 meaning that GPADC is busy. An RT conversion can unlock + * conversion will give 0 as a result. Bit GPADC_STATUS.GPADC_AVAILABLE + * will stay at 0 meaning that GPADC is busy. An RT conversion can unlock * the GPADC. * * Workaround(s): * To avoid the lock mechanism, the workaround to follow before any stop * conversion request is: - * Force the GPADC state machine to be ON by using the GPADC_CTRL1. - * GPADC_FORCE bit = 1 + * Force the GPADC state machine to be ON by using the + * GPADC_CTRL1.GPADC_FORCE bit = 1 * Shutdown the GPADC AUTO conversion using * GPADC_AUTO_CTRL.SHUTDOWN_CONV[01] = 0. * After 100us, force the GPADC state machine to be OFF by using the - * GPADC_CTRL1. GPADC_FORCE bit = 0 + * GPADC_CTRL1.GPADC_FORCE bit = 0 */ static int palmas_disable_auto_conversion(struct palmas_gpadc *adc) { @@ -141,13 +141,10 @@ static int palmas_disable_auto_conversion(struct palmas_gpadc *adc) return ret; } - ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE, - PALMAS_GPADC_AUTO_CTRL, - PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV1 | - PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV0, - 0); + ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE, + PALMAS_GPADC_AUTO_CTRL, 0); if (ret < 0) { - dev_err(adc->dev, "AUTO_CTRL update failed: %d\n", ret); + dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret); return ret; } @@ -174,9 +171,20 @@ static irqreturn_t palmas_gpadc_irq(int irq, void *data) static irqreturn_t palmas_gpadc_irq_auto(int irq, void *data) { struct palmas_gpadc *adc = data; + unsigned int val = 0; + int ret; + + ret = palmas_read(adc->palmas, PALMAS_INTERRUPT_BASE, + PALMAS_INT3_LINE_STATE, &val); + if (ret < 0) + dev_err(adc->dev, "%s: Failed to read INT3_LINE_STATE, %d\n", + __func__, ret); + + if (val & PALMAS_INT3_LINE_STATE_GPADC_AUTO_0) + dev_info(adc->dev, "Auto0 threshold interrupt occurred\n"); + if (val & PALMAS_INT3_LINE_STATE_GPADC_AUTO_1) + dev_info(adc->dev, "Auto1 threshold interrupt occurred\n"); - dev_info(adc->dev, "Threshold interrupt %d occurs\n", irq); - palmas_disable_auto_conversion(adc); return IRQ_HANDLED; } @@ -303,6 +311,12 @@ static int palmas_gpadc_auto_conv_reset(struct palmas_gpadc *adc) if (!adc->auto_conv0_enable && !adc->auto_conv1_enable) return 0; + ret = palmas_disable_auto_conversion(adc); + if (ret < 0) { + dev_err(adc->dev, "Disable auto conversion failed: %d\n", ret); + return ret; + } + ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE, PALMAS_GPADC_AUTO_SELECT, 0); if (ret < 0) { @@ -310,10 +324,58 @@ static int palmas_gpadc_auto_conv_reset(struct palmas_gpadc *adc) return ret; } - ret = palmas_disable_auto_conversion(adc); - if (ret < 0) { - dev_err(adc->dev, "Disable auto conversion failed: %d\n", ret); - return ret; + return 0; +} + +static int palmas_gpadc_check_status(struct palmas_gpadc *adc) +{ + int retry_cnt = 3; + int check_cnt = 3; + int loop_cnt = 3; + unsigned int val = 0; + int ret; + +retry: + do { + ret = palmas_read(adc->palmas, PALMAS_GPADC_BASE, + PALMAS_GPADC_STATUS, &val); + if (ret < 0) { + dev_err(adc->dev, "%s: Failed to read STATUS, %d\n", + __func__, ret); + return ret; + } else if (val & PALMAS_GPADC_STATUS_GPADC_AVAILABLE) { + if (--check_cnt == 0) + break; + } else { + dev_warn(adc->dev, "%s: GPADC is busy, STATUS 0x%02x\n", + __func__, val); + } + udelay(100); + } while (loop_cnt-- > 0); + + if (check_cnt == 0) { + if (retry_cnt < 3) + dev_warn(adc->dev, "%s: GPADC is unlocked.\n", + __func__); + return 0; + } + + dev_warn(adc->dev, "%s: GPADC is locked.\n", __func__); + dev_warn(adc->dev, "%s: Perform RT conversion to unlock GPADC.\n", + __func__); + palmas_disable_auto_conversion(adc); + palmas_write(adc->palmas, PALMAS_GPADC_BASE, PALMAS_GPADC_RT_SELECT, + PALMAS_GPADC_RT_SELECT_RT_CONV_EN); + palmas_write(adc->palmas, PALMAS_GPADC_BASE, PALMAS_GPADC_RT_CTRL, + PALMAS_GPADC_RT_CTRL_START_POLARITY); + udelay(100); + palmas_write(adc->palmas, PALMAS_GPADC_BASE, PALMAS_GPADC_RT_CTRL, 0); + palmas_write(adc->palmas, PALMAS_GPADC_BASE, PALMAS_GPADC_RT_SELECT, 0); + if (retry_cnt-- > 0) { + goto retry; + } else { + dev_err(adc->dev, "%s: Failed to unlock GPADC.\n", __func__); + return -EDEADLK; } return 0; @@ -381,11 +443,6 @@ static int palmas_gpadc_enable(struct palmas_gpadc *adc, int adc_chan, return ret; } } else { - ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE, - PALMAS_GPADC_SW_SELECT, 0); - if (ret < 0) - dev_err(adc->dev, "SW_SELECT write failed: %d\n", ret); - mask = val = 0; mask |= PALMAS_GPADC_CTRL1_GPADC_FORCE; @@ -491,6 +548,12 @@ static int palmas_gpadc_start_convertion(struct palmas_gpadc *adc, int adc_chan) } ret = (val & 0xFFF); + if (ret == 0) { + ret = palmas_gpadc_check_status(adc); + if (ret == 0) + ret = -EAGAIN; + } + return ret; } @@ -1036,6 +1099,11 @@ static int palmas_gpadc_probe(struct platform_device *pdev) if (adc->auto_conv0_enable || adc->auto_conv1_enable) device_wakeup_enable(&pdev->dev); + ret = palmas_gpadc_check_status(adc); + if (ret < 0) + goto out_irq_auto1_free; + + palmas_gpadc_auto_conv_reset(adc); ret = palmas_gpadc_auto_conv_configure(adc); if (ret < 0) { dev_err(adc->dev, "auto_conv_configure() failed: %d\n", ret); @@ -1080,6 +1148,15 @@ static int palmas_gpadc_remove(struct platform_device *pdev) return 0; } +static void palmas_gpadc_shutdown(struct platform_device *pdev) +{ + struct iio_dev *iodev = dev_get_drvdata(&pdev->dev); + struct palmas_gpadc *adc = iio_priv(iodev); + + if (adc->auto_conv0_enable || adc->auto_conv1_enable) + palmas_gpadc_auto_conv_reset(adc); +} + #ifdef CONFIG_PM_SLEEP static int palmas_gpadc_suspend(struct device *dev) { @@ -1132,6 +1209,7 @@ MODULE_DEVICE_TABLE(of, of_palmas_gpadc_match_tbl); static struct platform_driver palmas_gpadc_driver = { .probe = palmas_gpadc_probe, .remove = palmas_gpadc_remove, + .shutdown = palmas_gpadc_shutdown, .driver = { .name = MOD_NAME, .owner = THIS_MODULE, |