From 397b1dcc449082ce3f720c548da9c59db01cb739 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 22 Sep 2008 09:04:43 +0200 Subject: ALSA: oxygen: add UART I/O functions Add functions to allow model drivers to communicate with external chips by doing I/O with the not-used-for-MIDI UART. Signed-off-by: Clemens Ladisch --- sound/pci/oxygen/oxygen.h | 6 ++++++ sound/pci/oxygen/oxygen_io.c | 21 +++++++++++++++++++++ sound/pci/oxygen/oxygen_lib.c | 32 ++++++++++++++++++++++++++++++-- 3 files changed, 57 insertions(+), 2 deletions(-) diff --git a/sound/pci/oxygen/oxygen.h b/sound/pci/oxygen/oxygen.h index f82a962..19107c6 100644 --- a/sound/pci/oxygen/oxygen.h +++ b/sound/pci/oxygen/oxygen.h @@ -79,6 +79,7 @@ struct oxygen_model { void (*update_dac_volume)(struct oxygen *chip); void (*update_dac_mute)(struct oxygen *chip); void (*gpio_changed)(struct oxygen *chip); + void (*uart_input)(struct oxygen *chip); void (*ac97_switch)(struct oxygen *chip, unsigned int reg, unsigned int mute); const unsigned int *dac_tlv; @@ -125,6 +126,8 @@ struct oxygen { __le32 _32[OXYGEN_IO_SIZE / 4]; } saved_registers; u16 saved_ac97_registers[2][0x40]; + unsigned int uart_input_count; + u8 uart_input[32]; struct oxygen_model model; }; @@ -174,6 +177,9 @@ void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec, void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data); void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data); +void oxygen_reset_uart(struct oxygen *chip); +void oxygen_write_uart(struct oxygen *chip, u8 data); + static inline void oxygen_set_bits8(struct oxygen *chip, unsigned int reg, u8 value) { diff --git a/sound/pci/oxygen/oxygen_io.c b/sound/pci/oxygen/oxygen_io.c index 83f135f..deba738 100644 --- a/sound/pci/oxygen/oxygen_io.c +++ b/sound/pci/oxygen/oxygen_io.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include "oxygen.h" @@ -232,3 +233,23 @@ void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data) device | OXYGEN_2WIRE_DIR_WRITE); } EXPORT_SYMBOL(oxygen_write_i2c); + +static void _write_uart(struct oxygen *chip, unsigned int port, u8 data) +{ + if (oxygen_read8(chip, OXYGEN_MPU401 + 1) & MPU401_TX_FULL) + msleep(1); + oxygen_write8(chip, OXYGEN_MPU401 + port, data); +} + +void oxygen_reset_uart(struct oxygen *chip) +{ + _write_uart(chip, 1, MPU401_RESET); + _write_uart(chip, 1, MPU401_ENTER_UART); +} +EXPORT_SYMBOL(oxygen_reset_uart); + +void oxygen_write_uart(struct oxygen *chip, u8 data) +{ + _write_uart(chip, 0, data); +} +EXPORT_SYMBOL(oxygen_write_uart); diff --git a/sound/pci/oxygen/oxygen_lib.c b/sound/pci/oxygen/oxygen_lib.c index b199721..84f481d 100644 --- a/sound/pci/oxygen/oxygen_lib.c +++ b/sound/pci/oxygen/oxygen_lib.c @@ -35,6 +35,30 @@ MODULE_DESCRIPTION("C-Media CMI8788 helper library"); MODULE_LICENSE("GPL v2"); +static inline int oxygen_uart_input_ready(struct oxygen *chip) +{ + return !(oxygen_read8(chip, OXYGEN_MPU401 + 1) & MPU401_RX_EMPTY); +} + +static void oxygen_read_uart(struct oxygen *chip) +{ + if (unlikely(!oxygen_uart_input_ready(chip))) { + /* no data, but read it anyway to clear the interrupt */ + oxygen_read8(chip, OXYGEN_MPU401); + return; + } + do { + u8 data = oxygen_read8(chip, OXYGEN_MPU401); + if (data == MPU401_ACK) + continue; + if (chip->uart_input_count >= ARRAY_SIZE(chip->uart_input)) + chip->uart_input_count = 0; + chip->uart_input[chip->uart_input_count++] = data; + } while (oxygen_uart_input_ready(chip)); + if (chip->model.uart_input) + chip->model.uart_input(chip); +} + static irqreturn_t oxygen_interrupt(int dummy, void *dev_id) { struct oxygen *chip = dev_id; @@ -87,8 +111,12 @@ static irqreturn_t oxygen_interrupt(int dummy, void *dev_id) if (status & OXYGEN_INT_GPIO) schedule_work(&chip->gpio_work); - if ((status & OXYGEN_INT_MIDI) && chip->midi) - snd_mpu401_uart_interrupt(0, chip->midi->private_data); + if (status & OXYGEN_INT_MIDI) { + if (chip->midi) + snd_mpu401_uart_interrupt(0, chip->midi->private_data); + else + oxygen_read_uart(chip); + } if (status & OXYGEN_INT_AC97) wake_up(&chip->ac97_waitqueue); -- cgit v1.1