mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
306 lines
7.0 KiB
306 lines
7.0 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Copyright (C) 2016 Imagination Technologies |
|
* Author: Paul Burton <[email protected]> |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/io.h> |
|
#include <linux/mfd/syscon.h> |
|
#include <linux/module.h> |
|
#include <linux/of_address.h> |
|
#include <linux/of_platform.h> |
|
#include <linux/platform_device.h> |
|
#include <linux/regmap.h> |
|
#include <linux/slab.h> |
|
|
|
#include "line-display.h" |
|
|
|
struct img_ascii_lcd_ctx; |
|
|
|
/** |
|
* struct img_ascii_lcd_config - Configuration information about an LCD model |
|
* @num_chars: the number of characters the LCD can display |
|
* @external_regmap: true if registers are in a system controller, else false |
|
* @update: function called to update the LCD |
|
*/ |
|
struct img_ascii_lcd_config { |
|
unsigned int num_chars; |
|
bool external_regmap; |
|
void (*update)(struct linedisp *linedisp); |
|
}; |
|
|
|
/** |
|
* struct img_ascii_lcd_ctx - Private data structure |
|
* @base: the base address of the LCD registers |
|
* @regmap: the regmap through which LCD registers are accessed |
|
* @offset: the offset within regmap to the start of the LCD registers |
|
* @cfg: pointer to the LCD model configuration |
|
* @linedisp: line display structure |
|
* @curr: the string currently displayed on the LCD |
|
*/ |
|
struct img_ascii_lcd_ctx { |
|
union { |
|
void __iomem *base; |
|
struct regmap *regmap; |
|
}; |
|
u32 offset; |
|
const struct img_ascii_lcd_config *cfg; |
|
struct linedisp linedisp; |
|
char curr[] __aligned(8); |
|
}; |
|
|
|
/* |
|
* MIPS Boston development board |
|
*/ |
|
|
|
static void boston_update(struct linedisp *linedisp) |
|
{ |
|
struct img_ascii_lcd_ctx *ctx = |
|
container_of(linedisp, struct img_ascii_lcd_ctx, linedisp); |
|
ulong val; |
|
|
|
#if BITS_PER_LONG == 64 |
|
val = *((u64 *)&ctx->curr[0]); |
|
__raw_writeq(val, ctx->base); |
|
#elif BITS_PER_LONG == 32 |
|
val = *((u32 *)&ctx->curr[0]); |
|
__raw_writel(val, ctx->base); |
|
val = *((u32 *)&ctx->curr[4]); |
|
__raw_writel(val, ctx->base + 4); |
|
#else |
|
# error Not 32 or 64 bit |
|
#endif |
|
} |
|
|
|
static struct img_ascii_lcd_config boston_config = { |
|
.num_chars = 8, |
|
.update = boston_update, |
|
}; |
|
|
|
/* |
|
* MIPS Malta development board |
|
*/ |
|
|
|
static void malta_update(struct linedisp *linedisp) |
|
{ |
|
struct img_ascii_lcd_ctx *ctx = |
|
container_of(linedisp, struct img_ascii_lcd_ctx, linedisp); |
|
unsigned int i; |
|
int err = 0; |
|
|
|
for (i = 0; i < linedisp->num_chars; i++) { |
|
err = regmap_write(ctx->regmap, |
|
ctx->offset + (i * 8), ctx->curr[i]); |
|
if (err) |
|
break; |
|
} |
|
|
|
if (unlikely(err)) |
|
pr_err_ratelimited("Failed to update LCD display: %d\n", err); |
|
} |
|
|
|
static struct img_ascii_lcd_config malta_config = { |
|
.num_chars = 8, |
|
.external_regmap = true, |
|
.update = malta_update, |
|
}; |
|
|
|
/* |
|
* MIPS SEAD3 development board |
|
*/ |
|
|
|
enum { |
|
SEAD3_REG_LCD_CTRL = 0x00, |
|
#define SEAD3_REG_LCD_CTRL_SETDRAM BIT(7) |
|
SEAD3_REG_LCD_DATA = 0x08, |
|
SEAD3_REG_CPLD_STATUS = 0x10, |
|
#define SEAD3_REG_CPLD_STATUS_BUSY BIT(0) |
|
SEAD3_REG_CPLD_DATA = 0x18, |
|
#define SEAD3_REG_CPLD_DATA_BUSY BIT(7) |
|
}; |
|
|
|
static int sead3_wait_sm_idle(struct img_ascii_lcd_ctx *ctx) |
|
{ |
|
unsigned int status; |
|
int err; |
|
|
|
do { |
|
err = regmap_read(ctx->regmap, |
|
ctx->offset + SEAD3_REG_CPLD_STATUS, |
|
&status); |
|
if (err) |
|
return err; |
|
} while (status & SEAD3_REG_CPLD_STATUS_BUSY); |
|
|
|
return 0; |
|
|
|
} |
|
|
|
static int sead3_wait_lcd_idle(struct img_ascii_lcd_ctx *ctx) |
|
{ |
|
unsigned int cpld_data; |
|
int err; |
|
|
|
err = sead3_wait_sm_idle(ctx); |
|
if (err) |
|
return err; |
|
|
|
do { |
|
err = regmap_read(ctx->regmap, |
|
ctx->offset + SEAD3_REG_LCD_CTRL, |
|
&cpld_data); |
|
if (err) |
|
return err; |
|
|
|
err = sead3_wait_sm_idle(ctx); |
|
if (err) |
|
return err; |
|
|
|
err = regmap_read(ctx->regmap, |
|
ctx->offset + SEAD3_REG_CPLD_DATA, |
|
&cpld_data); |
|
if (err) |
|
return err; |
|
} while (cpld_data & SEAD3_REG_CPLD_DATA_BUSY); |
|
|
|
return 0; |
|
} |
|
|
|
static void sead3_update(struct linedisp *linedisp) |
|
{ |
|
struct img_ascii_lcd_ctx *ctx = |
|
container_of(linedisp, struct img_ascii_lcd_ctx, linedisp); |
|
unsigned int i; |
|
int err = 0; |
|
|
|
for (i = 0; i < linedisp->num_chars; i++) { |
|
err = sead3_wait_lcd_idle(ctx); |
|
if (err) |
|
break; |
|
|
|
err = regmap_write(ctx->regmap, |
|
ctx->offset + SEAD3_REG_LCD_CTRL, |
|
SEAD3_REG_LCD_CTRL_SETDRAM | i); |
|
if (err) |
|
break; |
|
|
|
err = sead3_wait_lcd_idle(ctx); |
|
if (err) |
|
break; |
|
|
|
err = regmap_write(ctx->regmap, |
|
ctx->offset + SEAD3_REG_LCD_DATA, |
|
ctx->curr[i]); |
|
if (err) |
|
break; |
|
} |
|
|
|
if (unlikely(err)) |
|
pr_err_ratelimited("Failed to update LCD display: %d\n", err); |
|
} |
|
|
|
static struct img_ascii_lcd_config sead3_config = { |
|
.num_chars = 16, |
|
.external_regmap = true, |
|
.update = sead3_update, |
|
}; |
|
|
|
static const struct of_device_id img_ascii_lcd_matches[] = { |
|
{ .compatible = "img,boston-lcd", .data = &boston_config }, |
|
{ .compatible = "mti,malta-lcd", .data = &malta_config }, |
|
{ .compatible = "mti,sead3-lcd", .data = &sead3_config }, |
|
{ /* sentinel */ } |
|
}; |
|
MODULE_DEVICE_TABLE(of, img_ascii_lcd_matches); |
|
|
|
/** |
|
* img_ascii_lcd_probe() - probe an LCD display device |
|
* @pdev: the LCD platform device |
|
* |
|
* Probe an LCD display device, ensuring that we have the required resources in |
|
* order to access the LCD & setting up private data as well as sysfs files. |
|
* |
|
* Return: 0 on success, else -ERRNO |
|
*/ |
|
static int img_ascii_lcd_probe(struct platform_device *pdev) |
|
{ |
|
const struct of_device_id *match; |
|
const struct img_ascii_lcd_config *cfg; |
|
struct device *dev = &pdev->dev; |
|
struct img_ascii_lcd_ctx *ctx; |
|
int err; |
|
|
|
match = of_match_device(img_ascii_lcd_matches, dev); |
|
if (!match) |
|
return -ENODEV; |
|
|
|
cfg = match->data; |
|
ctx = devm_kzalloc(dev, sizeof(*ctx) + cfg->num_chars, GFP_KERNEL); |
|
if (!ctx) |
|
return -ENOMEM; |
|
|
|
if (cfg->external_regmap) { |
|
ctx->regmap = syscon_node_to_regmap(dev->parent->of_node); |
|
if (IS_ERR(ctx->regmap)) |
|
return PTR_ERR(ctx->regmap); |
|
|
|
if (of_property_read_u32(dev->of_node, "offset", &ctx->offset)) |
|
return -EINVAL; |
|
} else { |
|
ctx->base = devm_platform_ioremap_resource(pdev, 0); |
|
if (IS_ERR(ctx->base)) |
|
return PTR_ERR(ctx->base); |
|
} |
|
|
|
err = linedisp_register(&ctx->linedisp, dev, cfg->num_chars, ctx->curr, |
|
cfg->update); |
|
if (err) |
|
return err; |
|
|
|
/* for backwards compatibility */ |
|
err = compat_only_sysfs_link_entry_to_kobj(&dev->kobj, |
|
&ctx->linedisp.dev.kobj, |
|
"message", NULL); |
|
if (err) |
|
goto err_unregister; |
|
|
|
platform_set_drvdata(pdev, ctx); |
|
return 0; |
|
|
|
err_unregister: |
|
linedisp_unregister(&ctx->linedisp); |
|
return err; |
|
} |
|
|
|
/** |
|
* img_ascii_lcd_remove() - remove an LCD display device |
|
* @pdev: the LCD platform device |
|
* |
|
* Remove an LCD display device, freeing private resources & ensuring that the |
|
* driver stops using the LCD display registers. |
|
* |
|
* Return: 0 |
|
*/ |
|
static int img_ascii_lcd_remove(struct platform_device *pdev) |
|
{ |
|
struct img_ascii_lcd_ctx *ctx = platform_get_drvdata(pdev); |
|
|
|
sysfs_remove_link(&pdev->dev.kobj, "message"); |
|
linedisp_unregister(&ctx->linedisp); |
|
return 0; |
|
} |
|
|
|
static struct platform_driver img_ascii_lcd_driver = { |
|
.driver = { |
|
.name = "img-ascii-lcd", |
|
.of_match_table = img_ascii_lcd_matches, |
|
}, |
|
.probe = img_ascii_lcd_probe, |
|
.remove = img_ascii_lcd_remove, |
|
}; |
|
module_platform_driver(img_ascii_lcd_driver); |
|
|
|
MODULE_DESCRIPTION("Imagination Technologies ASCII LCD Display"); |
|
MODULE_AUTHOR("Paul Burton <[email protected]>"); |
|
MODULE_LICENSE("GPL");
|
|
|