[E3-hacking] [RFC][PATCH v2 4/5] input: serio: add support for Amstrad Delta serial keyboard port
Dmitry Torokhov
dmitry.torokhov at gmail.com
Tue Mar 30 07:56:19 BST 2010
On Mon, Mar 29, 2010 at 04:30:41PM +0200, Janusz Krzysztofik wrote:
> The patch introduces a serio driver that supports a keyboard serial port found
> on the Amstrad Delta videophone board.
>
> After initializing the hardware, the driver reads its input data from a buffer
> filled in by the board FIQ (Fast Interrupt Request) handler.
>
> Standard AT keyboard driver (atkbd) will be used on top of the serio layer for
> handling the E3 keyboard (called mailboard) connected to the port. Since the
> device generated scancodes differ from what the atkbd expects, a custom key
> code to scan code table must be loaded from userspace for the keyboard to be
> useable.
>
> Compiles and works on to of patch 3/5:
> omap1: Amstrad Delta: use FIQ for processing GPIO interrupts
>
> Created and tested against linux-2.6.34-rc2.
>
> Signed-off-by: Janusz Krzysztofik <jkrzyszt at tis.icnet.pl>
> ---
> v2 changes:
> - use correct variable name for return value in ams_delta_kbd_init(),
> - remove scan code to key code mapping,
> - refreshed against linux-2.6.34-rc2.
>
> drivers/input/serio/Kconfig | 9 +
> drivers/input/serio/Makefile | 1
> drivers/input/serio/ams_delta_keyboard.c | 171 +++++++++++++++++++++++++++++++
> 3 files changed, 181 insertions(+)
>
> diff -uprN git.orig/drivers/input/serio/Kconfig git/drivers/input/serio/Kconfig
> --- git.orig/drivers/input/serio/Kconfig 2010-03-25 15:55:42.000000000 +0100
> +++ git/drivers/input/serio/Kconfig 2010-03-28 23:42:09.000000000 +0200
> @@ -209,4 +209,13 @@ config SERIO_ALTERA_PS2
> To compile this driver as a module, choose M here: the
> module will be called altera_ps2.
>
> +config SERIO_AMS_DELTA
> + tristate "Amstrad Delta (E3) keyboard support"
> + depends on MACH_AMS_DELTA && AMS_DELTA_FIQ
> + ---help---
> + Say Y here if has an E3 and want to use the separate keyboard
> +
> + To compile this driver as a module, choose M here: the
> + module will be called ams_delta_keyboard
> +
> endif
> diff -uprN git.orig/drivers/input/serio/Makefile git/drivers/input/serio/Makefile
> --- git.orig/drivers/input/serio/Makefile 2010-03-25 15:55:42.000000000 +0100
> +++ git/drivers/input/serio/Makefile 2010-03-28 23:42:09.000000000 +0200
> @@ -21,5 +21,6 @@ obj-$(CONFIG_SERIO_PCIPS2) += pcips2.o
> obj-$(CONFIG_SERIO_MACEPS2) += maceps2.o
> obj-$(CONFIG_SERIO_LIBPS2) += libps2.o
> obj-$(CONFIG_SERIO_RAW) += serio_raw.o
> +obj-$(CONFIG_SERIO_AMS_DELTA) += ams_delta_keyboard.o
> obj-$(CONFIG_SERIO_XILINX_XPS_PS2) += xilinx_ps2.o
> obj-$(CONFIG_SERIO_ALTERA_PS2) += altera_ps2.o
> diff -uprN git.orig/drivers/input/serio/ams_delta_keyboard.c git/drivers/input/serio/ams_delta_keyboard.c
> --- git.orig/drivers/input/serio/ams_delta_keyboard.c 1970-01-01 01:00:00.000000000 +0100
> +++ git/drivers/input/serio/ams_delta_keyboard.c 2010-03-28 23:42:09.000000000 +0200
> @@ -0,0 +1,171 @@
> +/*
> + * Amstrad E3 (delta) keyboard driver
> + *
> + * Copyright (c) 2006 Matt Callow
> + *
> + * 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.
> + *
> + * Thanks to Cliff Lawson for his help
> + *
> + * The Amstrad Delta keyboard (or mailboard) is connected to GPIO 0 (clock)
> + * and GPIO 1 (data). It uses normal PC-AT style serial transmission,
> + * but the data and clock lines are inverted on the E3 mainboard,
> + * and the scancodes produced are non-standard
> + *
> + * Due to the strict timing requirements of the interface,
> + * the serial data stream is read using a FIQ handler, and then
> + * the resulting byte stream passed to this driver via a circular buffer.
> + */
> +#include <linux/gpio.h>
> +#include <linux/init.h>
> +#include <linux/irq.h>
> +#include <linux/module.h>
> +#include <linux/serio.h>
> +#include <asm/fiq.h>
> +#include <plat/board-ams-delta.h>
> +#include <mach/ams-delta-fiq.h>
> +
> +MODULE_AUTHOR("Matt Callow");
> +MODULE_DESCRIPTION("AMS Delta (E3) Keyboard driver");
> +MODULE_LICENSE("GPL");
> +
> +#define MAX_SCANCODE 0x84
Not needed anymore?
> +
> +static struct serio *ams_delta_kbd_port;
> +
> +static int check_data(int data)
> +{
> + int i;
> + int parity = 0;
> +
> + /* check valid stop bit */
> + if (!(data & 0x400)) {
> + printk(KERN_WARNING
> + "Invalid stop bit in AMS keyboard"
> + " data=0x%X\r\n", data);
Consider switching top dev_err(), dev_warning(), etc. Also do not split
text strings, even if you run over 80 column limit. BTW, why "\r\n" in
the message?
> + return 0;
> + }
> + /* calculate the parity */
> + for (i = 1; i < 10; i++) {
> + if (data & (1 << i))
> + parity++;
> + }
> + /* it should be odd */
> + if (!(parity & 0x01)) {
> + printk(KERN_WARNING
> + "Paritiy check failed in AMS keyboard "
> + " data=0x%X parity 0x%X\r\n", data, parity);
> + }
> + return 1;
> +}
> +
> +static irqreturn_t ams_delta_kbd_interrupt(int irq, void *dev_id,
> + struct pt_regs *regs)
> +{
> + int *circ_buff = &fiq_buffer[FIQ_CIRC_BUFF];
> + /*
> + * Read data from the CIRC buffer, check it, translate the scancode
> + * and then pass it on the serio
> + */
> + fiq_buffer[FIQ_IRQ_PEND] = 0;
> +
> + while (fiq_buffer[FIQ_CHAR_CNT] > 0) {
> + int data;
> + u8 scancode;
> +
> + data = circ_buff[fiq_buffer[FIQ_BACK_OFFSET]] ;
> + fiq_buffer[FIQ_BACK_OFFSET]++;
> + fiq_buffer[FIQ_CHAR_CNT]--;
> + if (fiq_buffer[FIQ_BACK_OFFSET] == fiq_buffer[FIQ_BUF_LEN])
> + fiq_buffer[FIQ_BACK_OFFSET] = 0;
> +
> + if (check_data(data)) {
> + scancode = (u8) (data >> 1) & 0xFF;
> + serio_interrupt(ams_delta_kbd_port, scancode, 0);
> + }
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static struct serio * __init ams_delta_kbd_allocate_serio(void)
> +{
> + struct serio *serio;
> +
> + serio = kmalloc(sizeof(struct serio), GFP_KERNEL);
kzalloc() please.
> + if (serio) {
> + memset(serio, 0, sizeof(struct serio));
> + serio->id.type = SERIO_8042;
> + strlcpy(serio->name, "AMS DELTA keyboard adapter",
> + sizeof(serio->name));
> + snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", "GPIO");
strlcpy(serio->phys, "GPIO/serio0", sizeof(serio->phys)); ?
> + }
> +
> + return serio;
> +}
> +
> +static int __init ams_delta_kbd_init(void)
> +{
> + int err;
> +
> + ams_delta_kbd_port = ams_delta_kbd_allocate_serio();
> + if (!ams_delta_kbd_port) {
> + err = -ENOMEM;
> + goto err;
> + }
> +
> + if (gpio_request(AMS_DELTA_GPIO_PIN_KEYBRD_DATA, "kbd-data")) {
> + printk(KERN_ERR "Couldn't request gpio pin for keyboard data");
> + err = -EINVAL;
Why do you mangle return value of gpio_request()? Just return what it
reported. Same goes for request_irq() below.
> + goto serio;
> + }
> + gpio_direction_input(AMS_DELTA_GPIO_PIN_KEYBRD_DATA);
> +
> + if (gpio_request(AMS_DELTA_GPIO_PIN_KEYBRD_CLK, "kbd-clock")) {
> + printk(KERN_ERR "Couldn't request gpio pin for keyboard clock");
> + err = -EINVAL;
> + goto gpio_data;
> + }
> + gpio_direction_input(AMS_DELTA_GPIO_PIN_KEYBRD_CLK);
> +
> + if (request_irq(OMAP_GPIO_IRQ(AMS_DELTA_GPIO_PIN_KEYBRD_CLK),
> + ams_delta_kbd_interrupt, 0, "ams-delta-keyboard", 0) < 0) {
> + printk(KERN_ERR "Couldn't request gpio interrupt %d",
> + OMAP_GPIO_IRQ(AMS_DELTA_GPIO_PIN_KEYBRD_CLK));
> + err = -EINVAL;
> + goto gpio_clk;
> + }
> + set_irq_type(OMAP_GPIO_IRQ(AMS_DELTA_GPIO_PIN_KEYBRD_CLK),
> + IRQ_TYPE_EDGE_RISING);
> +
> + /* enable keyboard */
> + ams_delta_latch2_write(AMD_DELTA_LATCH2_KEYBRD_PWR,
> + AMD_DELTA_LATCH2_KEYBRD_PWR);
This shoukd probably go into open() method of the serio port.
> +
> + serio_register_port(ams_delta_kbd_port);
> + printk(KERN_INFO "serio: AMS DELTA keyboard adapter\n");
> +
> + return 0;
> +gpio_clk:
> + gpio_free(AMS_DELTA_GPIO_PIN_KEYBRD_CLK);
> +gpio_data:
> + gpio_free(AMS_DELTA_GPIO_PIN_KEYBRD_DATA);
> +serio:
> + kfree(ams_delta_kbd_port);
> +err:
> + return err;
> +}
> +module_init(ams_delta_kbd_init);
> +
> +static void __exit ams_delta_kbd_exit(void)
> +{
> + serio_unregister_port(ams_delta_kbd_port);
> + /* disable keyboard */
> + ams_delta_latch2_write(AMD_DELTA_LATCH2_KEYBRD_PWR, 0);
And this into close().
> + free_irq(OMAP_GPIO_IRQ(AMS_DELTA_GPIO_PIN_KEYBRD_CLK), 0);
> + gpio_free(AMS_DELTA_GPIO_PIN_KEYBRD_CLK);
> + gpio_free(AMS_DELTA_GPIO_PIN_KEYBRD_DATA);
> + kfree(ams_delta_kbd_port);
> +}
> +module_exit(ams_delta_kbd_exit);
Thanks.
--
Dmitry
More information about the e3-hacking
mailing list