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linux/arch/arm/mach-ixp4xx/vulcan-setup.c
Linus Walleij e0fc62a655 w1: w1-gpio: Convert to use GPIO descriptors 
The w1 master driver includes a complete open drain emulation
reimplementation among other things.

This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.

When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.

As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.

w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.

The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.

To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.

We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-08 15:32:53 +01:00

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// SPDX-License-Identifier: GPL-2.0
/*
* arch/arm/mach-ixp4xx/vulcan-setup.c
*
* Arcom/Eurotech Vulcan board-setup
*
* Copyright (C) 2010 Marc Zyngier <maz@misterjones.org>
*
* based on fsg-setup.c:
* Copyright (C) 2008 Rod Whitby <rod@whitby.id.au>
*/
#include <linux/if_ether.h>
#include <linux/irq.h>
#include <linux/serial.h>
#include <linux/serial_8250.h>
#include <linux/io.h>
#include <linux/w1-gpio.h>
#include <linux/gpio/machine.h>
#include <linux/mtd/plat-ram.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/flash.h>
static struct flash_platform_data vulcan_flash_data = {
.map_name = "cfi_probe",
.width = 2,
};
static struct resource vulcan_flash_resource = {
.flags = IORESOURCE_MEM,
};
static struct platform_device vulcan_flash = {
.name = "IXP4XX-Flash",
.id = 0,
.dev = {
.platform_data = &vulcan_flash_data,
},
.resource = &vulcan_flash_resource,
.num_resources = 1,
};
static struct platdata_mtd_ram vulcan_sram_data = {
.mapname = "Vulcan SRAM",
.bankwidth = 1,
};
static struct resource vulcan_sram_resource = {
.flags = IORESOURCE_MEM,
};
static struct platform_device vulcan_sram = {
.name = "mtd-ram",
.id = 0,
.dev = {
.platform_data = &vulcan_sram_data,
},
.resource = &vulcan_sram_resource,
.num_resources = 1,
};
static struct resource vulcan_uart_resources[] = {
[0] = {
.start = IXP4XX_UART1_BASE_PHYS,
.end = IXP4XX_UART1_BASE_PHYS + 0x0fff,
.flags = IORESOURCE_MEM,
},
[1] = {
.start = IXP4XX_UART2_BASE_PHYS,
.end = IXP4XX_UART2_BASE_PHYS + 0x0fff,
.flags = IORESOURCE_MEM,
},
[2] = {
.flags = IORESOURCE_MEM,
},
};
static struct plat_serial8250_port vulcan_uart_data[] = {
[0] = {
.mapbase = IXP4XX_UART1_BASE_PHYS,
.membase = (char *)IXP4XX_UART1_BASE_VIRT + REG_OFFSET,
.irq = IRQ_IXP4XX_UART1,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = IXP4XX_UART_XTAL,
},
[1] = {
.mapbase = IXP4XX_UART2_BASE_PHYS,
.membase = (char *)IXP4XX_UART2_BASE_VIRT + REG_OFFSET,
.irq = IRQ_IXP4XX_UART2,
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
.iotype = UPIO_MEM,
.regshift = 2,
.uartclk = IXP4XX_UART_XTAL,
},
[2] = {
.irq = IXP4XX_GPIO_IRQ(4),
.irqflags = IRQF_TRIGGER_LOW,
.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
.iotype = UPIO_MEM,
.uartclk = 1843200,
},
[3] = {
.irq = IXP4XX_GPIO_IRQ(4),
.irqflags = IRQF_TRIGGER_LOW,
.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
.iotype = UPIO_MEM,
.uartclk = 1843200,
},
{ }
};
static struct platform_device vulcan_uart = {
.name = "serial8250",
.id = PLAT8250_DEV_PLATFORM,
.dev = {
.platform_data = vulcan_uart_data,
},
.resource = vulcan_uart_resources,
.num_resources = ARRAY_SIZE(vulcan_uart_resources),
};
static struct eth_plat_info vulcan_plat_eth[] = {
[0] = {
.phy = 0,
.rxq = 3,
.txreadyq = 20,
},
[1] = {
.phy = 1,
.rxq = 4,
.txreadyq = 21,
},
};
static struct platform_device vulcan_eth[] = {
[0] = {
.name = "ixp4xx_eth",
.id = IXP4XX_ETH_NPEB,
.dev = {
.platform_data = &vulcan_plat_eth[0],
},
},
[1] = {
.name = "ixp4xx_eth",
.id = IXP4XX_ETH_NPEC,
.dev = {
.platform_data = &vulcan_plat_eth[1],
},
},
};
static struct resource vulcan_max6369_resource = {
.flags = IORESOURCE_MEM,
};
static struct platform_device vulcan_max6369 = {
.name = "max6369_wdt",
.id = -1,
.resource = &vulcan_max6369_resource,
.num_resources = 1,
};
static struct gpiod_lookup_table vulcan_w1_gpiod_table = {
.dev_id = "w1-gpio",
.table = {
GPIO_LOOKUP_IDX("IXP4XX_GPIO_CHIP", 14, NULL, 0,
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN),
},
};
static struct w1_gpio_platform_data vulcan_w1_gpio_pdata = {
/* Intentionally left blank */
};
static struct platform_device vulcan_w1_gpio = {
.name = "w1-gpio",
.id = 0,
.dev = {
.platform_data = &vulcan_w1_gpio_pdata,
},
};
static struct platform_device *vulcan_devices[] __initdata = {
&vulcan_uart,
&vulcan_flash,
&vulcan_sram,
&vulcan_max6369,
&vulcan_eth[0],
&vulcan_eth[1],
&vulcan_w1_gpio,
};
static void __init vulcan_init(void)
{
ixp4xx_sys_init();
/* Flash is spread over both CS0 and CS1 */
vulcan_flash_resource.start = IXP4XX_EXP_BUS_BASE(0);
vulcan_flash_resource.end = IXP4XX_EXP_BUS_BASE(0) + SZ_32M - 1;
*IXP4XX_EXP_CS0 = IXP4XX_EXP_BUS_CS_EN |
IXP4XX_EXP_BUS_STROBE_T(3) |
IXP4XX_EXP_BUS_SIZE(0xF) |
IXP4XX_EXP_BUS_BYTE_RD16 |
IXP4XX_EXP_BUS_WR_EN;
*IXP4XX_EXP_CS1 = *IXP4XX_EXP_CS0;
/* SRAM on CS2, (256kB, 8bit, writable) */
vulcan_sram_resource.start = IXP4XX_EXP_BUS_BASE(2);
vulcan_sram_resource.end = IXP4XX_EXP_BUS_BASE(2) + SZ_256K - 1;
*IXP4XX_EXP_CS2 = IXP4XX_EXP_BUS_CS_EN |
IXP4XX_EXP_BUS_STROBE_T(1) |
IXP4XX_EXP_BUS_HOLD_T(2) |
IXP4XX_EXP_BUS_SIZE(9) |
IXP4XX_EXP_BUS_SPLT_EN |
IXP4XX_EXP_BUS_WR_EN |
IXP4XX_EXP_BUS_BYTE_EN;
/* XR16L2551 on CS3 (Moto style, 512 bytes, 8bits, writable) */
vulcan_uart_resources[2].start = IXP4XX_EXP_BUS_BASE(3);
vulcan_uart_resources[2].end = IXP4XX_EXP_BUS_BASE(3) + 16 - 1;
vulcan_uart_data[2].mapbase = vulcan_uart_resources[2].start;
vulcan_uart_data[3].mapbase = vulcan_uart_data[2].mapbase + 8;
*IXP4XX_EXP_CS3 = IXP4XX_EXP_BUS_CS_EN |
IXP4XX_EXP_BUS_STROBE_T(3) |
IXP4XX_EXP_BUS_CYCLES(IXP4XX_EXP_BUS_CYCLES_MOTOROLA)|
IXP4XX_EXP_BUS_WR_EN |
IXP4XX_EXP_BUS_BYTE_EN;
/* GPIOS on CS4 (512 bytes, 8bits, writable) */
*IXP4XX_EXP_CS4 = IXP4XX_EXP_BUS_CS_EN |
IXP4XX_EXP_BUS_WR_EN |
IXP4XX_EXP_BUS_BYTE_EN;
/* max6369 on CS5 (512 bytes, 8bits, writable) */
vulcan_max6369_resource.start = IXP4XX_EXP_BUS_BASE(5);
vulcan_max6369_resource.end = IXP4XX_EXP_BUS_BASE(5);
*IXP4XX_EXP_CS5 = IXP4XX_EXP_BUS_CS_EN |
IXP4XX_EXP_BUS_WR_EN |
IXP4XX_EXP_BUS_BYTE_EN;
gpiod_add_lookup_table(&vulcan_w1_gpiod_table);
platform_add_devices(vulcan_devices, ARRAY_SIZE(vulcan_devices));
}
MACHINE_START(ARCOM_VULCAN, "Arcom/Eurotech Vulcan")
/* Maintainer: Marc Zyngier <maz@misterjones.org> */
.map_io = ixp4xx_map_io,
.init_early = ixp4xx_init_early,
.init_irq = ixp4xx_init_irq,
.init_time = ixp4xx_timer_init,
.atag_offset = 0x100,
.init_machine = vulcan_init,
#if defined(CONFIG_PCI)
.dma_zone_size = SZ_64M,
#endif
.restart = ixp4xx_restart,
MACHINE_END
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