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OpenCloudOS-Kernel/include/linux/dma/hsu.h

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dmaengine: append hsu DMA driver The HSU DMA is developed to support High Speed UART controllers found in particular on Intel MID platforms such as Intel Medfield. The existing implementation is tighten to the drivers/tty/serial/mfd.c driver and has a lot of disadvantages. Besides that we would like to get rid of the old HS UART driver in regarding to extending the 8250 which supports generic DMAEngine API. That's why the current driver has been developed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-23 22:24:42 +08:00
/*
* Driver for the High Speed UART DMA
*
* Copyright (C) 2015 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _DMA_HSU_H
#define _DMA_HSU_H
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/platform_data/dma-hsu.h>
struct hsu_dma;
/**
* struct hsu_dma_chip - representation of HSU DMA hardware
* @dev: struct device of the DMA controller
* @irq: irq line
* @regs: memory mapped I/O space
* @length: I/O space length
* @offset: offset of the I/O space where registers are located
* @hsu: struct hsu_dma that is filed by ->probe()
* @pdata: platform data for the DMA controller if provided
*/
struct hsu_dma_chip {
struct device *dev;
int irq;
void __iomem *regs;
unsigned int length;
unsigned int offset;
struct hsu_dma *hsu;
};
dmaengine: hsu: introduce stubs for the exported functions This allows UART drivers to register HSU DMA Engine without being forced to use ifdefs. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 18:29:04 +08:00
#if IS_ENABLED(CONFIG_HSU_DMA)
dmaengine: append hsu DMA driver The HSU DMA is developed to support High Speed UART controllers found in particular on Intel MID platforms such as Intel Medfield. The existing implementation is tighten to the drivers/tty/serial/mfd.c driver and has a lot of disadvantages. Besides that we would like to get rid of the old HS UART driver in regarding to extending the 8250 which supports generic DMAEngine API. That's why the current driver has been developed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-23 22:24:42 +08:00
/* Export to the internal users */
dmaengine: hsu: Export hsu_dma_get_status() To allow other code to safely read DMA Channel Status Register (where the register attribute for Channel Error, Descriptor Time Out & Descriptor Done fields are read-clear), export hsu_dma_get_status(). hsu_dma_irq() is renamed to hsu_dma_do_irq() and requires Status Register value to be passed in. Signed-off-by: Chuah, Kim Tatt <kim.tatt.chuah@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-15 13:44:11 +08:00
int hsu_dma_get_status(struct hsu_dma_chip *chip, unsigned short nr,
u32 *status);
dmaengine: hsu: refactor hsu_dma_do_irq() to return int Since we have nice macro IRQ_RETVAL() we would use it to convert a flag of handled interrupt from int to irqreturn_t. The rationale of doing this is: a) hence we implicitly mark hsu_dma_do_irq() as an auxiliary function that can't be used as interrupt handler directly, and b) to be in align with serial driver which is using serial8250_handle_irq() that returns plain int by design. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-23 21:09:40 +08:00
int hsu_dma_do_irq(struct hsu_dma_chip *chip, unsigned short nr, u32 status);
dmaengine: append hsu DMA driver The HSU DMA is developed to support High Speed UART controllers found in particular on Intel MID platforms such as Intel Medfield. The existing implementation is tighten to the drivers/tty/serial/mfd.c driver and has a lot of disadvantages. Besides that we would like to get rid of the old HS UART driver in regarding to extending the 8250 which supports generic DMAEngine API. That's why the current driver has been developed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-23 22:24:42 +08:00
/* Export to the platform drivers */
int hsu_dma_probe(struct hsu_dma_chip *chip);
int hsu_dma_remove(struct hsu_dma_chip *chip);
dmaengine: hsu: introduce stubs for the exported functions This allows UART drivers to register HSU DMA Engine without being forced to use ifdefs. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 18:29:04 +08:00
#else
dmaengine: hsu: Export hsu_dma_get_status() To allow other code to safely read DMA Channel Status Register (where the register attribute for Channel Error, Descriptor Time Out & Descriptor Done fields are read-clear), export hsu_dma_get_status(). hsu_dma_irq() is renamed to hsu_dma_do_irq() and requires Status Register value to be passed in. Signed-off-by: Chuah, Kim Tatt <kim.tatt.chuah@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-15 13:44:11 +08:00
static inline int hsu_dma_get_status(struct hsu_dma_chip *chip,
unsigned short nr, u32 *status)
{
return 0;
}
dmaengine: hsu: refactor hsu_dma_do_irq() to return int Since we have nice macro IRQ_RETVAL() we would use it to convert a flag of handled interrupt from int to irqreturn_t. The rationale of doing this is: a) hence we implicitly mark hsu_dma_do_irq() as an auxiliary function that can't be used as interrupt handler directly, and b) to be in align with serial driver which is using serial8250_handle_irq() that returns plain int by design. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-23 21:09:40 +08:00
static inline int hsu_dma_do_irq(struct hsu_dma_chip *chip, unsigned short nr,
u32 status)
dmaengine: hsu: introduce stubs for the exported functions This allows UART drivers to register HSU DMA Engine without being forced to use ifdefs. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 18:29:04 +08:00
{
dmaengine: hsu: refactor hsu_dma_do_irq() to return int Since we have nice macro IRQ_RETVAL() we would use it to convert a flag of handled interrupt from int to irqreturn_t. The rationale of doing this is: a) hence we implicitly mark hsu_dma_do_irq() as an auxiliary function that can't be used as interrupt handler directly, and b) to be in align with serial driver which is using serial8250_handle_irq() that returns plain int by design. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-23 21:09:40 +08:00
return 0;
dmaengine: hsu: introduce stubs for the exported functions This allows UART drivers to register HSU DMA Engine without being forced to use ifdefs. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 18:29:04 +08:00
}
static inline int hsu_dma_probe(struct hsu_dma_chip *chip) { return -ENODEV; }
static inline int hsu_dma_remove(struct hsu_dma_chip *chip) { return 0; }
#endif /* CONFIG_HSU_DMA */
dmaengine: append hsu DMA driver The HSU DMA is developed to support High Speed UART controllers found in particular on Intel MID platforms such as Intel Medfield. The existing implementation is tighten to the drivers/tty/serial/mfd.c driver and has a lot of disadvantages. Besides that we would like to get rid of the old HS UART driver in regarding to extending the 8250 which supports generic DMAEngine API. That's why the current driver has been developed. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-23 22:24:42 +08:00
#endif /* _DMA_HSU_H */