kernel-fxtec-pro1x/include/drm/tinydrm/mipi-dbi.h
Noralf Trønnes b6bc202494 tinydrm/mipi-dbi: Use dma-safe buffers for all SPI transfers
[ Upstream commit a89bfc5d9a0732d84b4de311e27133daa0586316 ]

Buffers passed to spi_sync() must be dma-safe even for tiny buffers since
some SPI controllers use DMA for all transfers.

Example splat with CONFIG_DMA_API_DEBUG enabled:

[   23.750467] DMA-API: dw_dmac_pci 0000:00:15.0: device driver maps memory from stack [probable addr=000000001e49185d]
[   23.750529] WARNING: CPU: 1 PID: 1296 at kernel/dma/debug.c:1161 check_for_stack+0xb7/0x190
[   23.750533] Modules linked in: mmc_block(+) spi_pxa2xx_platform(+) pwm_lpss_pci pwm_lpss spi_pxa2xx_pci sdhci_pci cqhci intel_mrfld_pwrbtn extcon_intel_mrfld sdhci intel_mrfld_adc led_class mmc_core ili9341 mipi_dbi tinydrm backlight ti_ads7950 industrialio_triggered_buffer kfifo_buf intel_soc_pmic_mrfld hci_uart btbcm
[   23.750599] CPU: 1 PID: 1296 Comm: modprobe Not tainted 5.0.0-rc7+ #236
[   23.750605] Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48
[   23.750620] RIP: 0010:check_for_stack+0xb7/0x190
[   23.750630] Code: 8b 6d 50 4d 85 ed 75 04 4c 8b 6d 10 48 89 ef e8 2f 8b 44 00 48 89 c6 4a 8d 0c 23 4c 89 ea 48 c7 c7 88 d0 82 b4 e8 40 7c f9 ff <0f> 0b 8b 05 79 00 4b 01 85 c0 74 07 5b 5d 41 5c 41 5d c3 8b 05 54
[   23.750637] RSP: 0000:ffff97bbc0292fa0 EFLAGS: 00010286
[   23.750646] RAX: 0000000000000000 RBX: ffff97bbc0290000 RCX: 0000000000000006
[   23.750652] RDX: 0000000000000007 RSI: 0000000000000002 RDI: ffff94b33e115450
[   23.750658] RBP: ffff94b33c8578b0 R08: 0000000000000002 R09: 00000000000201c0
[   23.750664] R10: 00000006ecb0ccc6 R11: 0000000000034f38 R12: 000000000000316c
[   23.750670] R13: ffff94b33c84b250 R14: ffff94b33dedd5a0 R15: 0000000000000001
[   23.750679] FS:  0000000000000000(0000) GS:ffff94b33e100000(0063) knlGS:00000000f7faf690
[   23.750686] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
[   23.750691] CR2: 00000000f7f54faf CR3: 000000000722c000 CR4: 00000000001006e0
[   23.750696] Call Trace:
[   23.750713]  debug_dma_map_sg+0x100/0x340
[   23.750727]  ? dma_direct_map_sg+0x3b/0xb0
[   23.750739]  spi_map_buf+0x25a/0x300
[   23.750751]  __spi_pump_messages+0x2a4/0x680
[   23.750762]  __spi_sync+0x1dd/0x1f0
[   23.750773]  spi_sync+0x26/0x40
[   23.750790]  mipi_dbi_typec3_command_read+0x14d/0x240 [mipi_dbi]
[   23.750802]  ? spi_finalize_current_transfer+0x10/0x10
[   23.750821]  mipi_dbi_typec3_command+0x1bc/0x1d0 [mipi_dbi]

Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190222124329.23046-1-noralf@tronnes.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:32 -07:00

109 lines
3.5 KiB
C

/*
* MIPI Display Bus Interface (DBI) LCD controller support
*
* Copyright 2016 Noralf Trønnes
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __LINUX_MIPI_DBI_H
#define __LINUX_MIPI_DBI_H
#include <drm/tinydrm/tinydrm.h>
struct spi_device;
struct gpio_desc;
struct regulator;
/**
* struct mipi_dbi - MIPI DBI controller
* @tinydrm: tinydrm base
* @spi: SPI device
* @enabled: Pipeline is enabled
* @cmdlock: Command lock
* @command: Bus specific callback executing commands.
* @read_commands: Array of read commands terminated by a zero entry.
* Reading is disabled if this is NULL.
* @dc: Optional D/C gpio.
* @tx_buf: Buffer used for transfer (copy clip rect area)
* @tx_buf9: Buffer used for Option 1 9-bit conversion
* @tx_buf9_len: Size of tx_buf9.
* @swap_bytes: Swap bytes in buffer before transfer
* @reset: Optional reset gpio
* @rotation: initial rotation in degrees Counter Clock Wise
* @backlight: backlight device (optional)
* @regulator: power regulator (optional)
*/
struct mipi_dbi {
struct tinydrm_device tinydrm;
struct spi_device *spi;
bool enabled;
struct mutex cmdlock;
int (*command)(struct mipi_dbi *mipi, u8 *cmd, u8 *param, size_t num);
const u8 *read_commands;
struct gpio_desc *dc;
u16 *tx_buf;
void *tx_buf9;
size_t tx_buf9_len;
bool swap_bytes;
struct gpio_desc *reset;
unsigned int rotation;
struct backlight_device *backlight;
struct regulator *regulator;
};
static inline struct mipi_dbi *
mipi_dbi_from_tinydrm(struct tinydrm_device *tdev)
{
return container_of(tdev, struct mipi_dbi, tinydrm);
}
int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi,
struct gpio_desc *dc);
int mipi_dbi_init(struct device *dev, struct mipi_dbi *mipi,
const struct drm_simple_display_pipe_funcs *pipe_funcs,
struct drm_driver *driver,
const struct drm_display_mode *mode, unsigned int rotation);
void mipi_dbi_enable_flush(struct mipi_dbi *mipi,
struct drm_crtc_state *crtc_state,
struct drm_plane_state *plan_state);
void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe);
void mipi_dbi_hw_reset(struct mipi_dbi *mipi);
bool mipi_dbi_display_is_on(struct mipi_dbi *mipi);
int mipi_dbi_poweron_reset(struct mipi_dbi *mipi);
int mipi_dbi_poweron_conditional_reset(struct mipi_dbi *mipi);
u32 mipi_dbi_spi_cmd_max_speed(struct spi_device *spi, size_t len);
int mipi_dbi_command_read(struct mipi_dbi *mipi, u8 cmd, u8 *val);
int mipi_dbi_command_buf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len);
int mipi_dbi_command_stackbuf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len);
int mipi_dbi_buf_copy(void *dst, struct drm_framebuffer *fb,
struct drm_clip_rect *clip, bool swap);
/**
* mipi_dbi_command - MIPI DCS command with optional parameter(s)
* @mipi: MIPI structure
* @cmd: Command
* @seq...: Optional parameter(s)
*
* Send MIPI DCS command to the controller. Use mipi_dbi_command_read() for
* get/read.
*
* Returns:
* Zero on success, negative error code on failure.
*/
#define mipi_dbi_command(mipi, cmd, seq...) \
({ \
u8 d[] = { seq }; \
mipi_dbi_command_stackbuf(mipi, cmd, d, ARRAY_SIZE(d)); \
})
#ifdef CONFIG_DEBUG_FS
int mipi_dbi_debugfs_init(struct drm_minor *minor);
#else
#define mipi_dbi_debugfs_init NULL
#endif
#endif /* __LINUX_MIPI_DBI_H */