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From: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH v3 04/14] drivers: pinctrl: Add pinctrl driver for Microchip PIC32.
Date: Wed, 13 Jan 2016 14:42:22 +0100	[thread overview]
Message-ID: <1452692542.3931.9.camel@gmail.com> (raw)
In-Reply-To: <1452593909-16184-5-git-send-email-purna.mandal@microchip.com>

Am Dienstag, den 12.01.2016, 15:48 +0530 schrieb Purna Chandra Mandal:
> In PIC32 pin-controller is a combined gpio-controller, pin-mux and
> pin-config module. Remappable peripherals are assigned pins through
> per-pin based muxing logic. And pin configuration are performed on
> specific port registers which are shared along with gpio controller.
> Note, non-remappable peripherals have default pins assigned thus
> require
> no muxing.
> 
> Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
> 

Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

> 
> ---
> 
> Changes in v3:
> - read register base from device-tree
> - add/update comments to explain how pinctrl'r works.
> - replace pic32_ioremap() with ioremap().
> 
> Changes in v2:
> - add pinconf routine for configuring pin property
> 
>  drivers/pinctrl/Kconfig         |   9 +
>  drivers/pinctrl/Makefile        |   1 +
>  drivers/pinctrl/pinctrl_pic32.c | 363
> ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 373 insertions(+)
>  create mode 100644 drivers/pinctrl/pinctrl_pic32.c
> 
> diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
> index 57e6142..292c4e2 100644
> --- a/drivers/pinctrl/Kconfig
> +++ b/drivers/pinctrl/Kconfig
> @@ -131,6 +131,15 @@ config PINCTRL_SANDBOX
>  	  actually does nothing but print debug messages when
> pinctrl
>  	  operations are invoked.
>  
> +config PIC32_PINCTRL
> +	bool "Microchip PIC32 pin-control and pin-mux driver"
> +	depends on DM && MACH_PIC32
> +	help
> +	  Supports individual pin selection and configuration for
> each remappable
> +	  peripheral available on Microchip PIC32 SoCs. This driver
> is controlled
> +	  by a device tree node which contains both GPIO defintion
> and pin control
> +	  functions.
> +
>  endif
>  
>  source "drivers/pinctrl/uniphier/Kconfig"
> diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
> index 70d25dc..b4f4650 100644
> --- a/drivers/pinctrl/Makefile
> +++ b/drivers/pinctrl/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
>  obj-$(CONFIG_PINCTRL_SANDBOX)	+= pinctrl-sandbox.o
>  
>  obj-$(CONFIG_ARCH_UNIPHIER)	+= uniphier/
> +obj-$(CONFIG_PIC32_PINCTRL)	+= pinctrl_pic32.o
> diff --git a/drivers/pinctrl/pinctrl_pic32.c
> b/drivers/pinctrl/pinctrl_pic32.c
> new file mode 100644
> index 0000000..5cf97ec
> --- /dev/null
> +++ b/drivers/pinctrl/pinctrl_pic32.c
> @@ -0,0 +1,363 @@
> +/*
> + * Pinctrl driver for Microchip PIC32 SoCs
> + * Copyright (c) 2015 Microchip Technology Inc.
> + * Written by Purna Chandra Mandal <purna.mandal@microchip.com>
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +#include <common.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <asm/io.h>
> +#include <dm/pinctrl.h>
> +#include <dm/root.h>
> +#include <mach/pic32.h>
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +/* PIC32 has 10 peripheral ports with 16 pins each.
> + * Ports are marked PORTA-PORTK or PORT0-PORT9.
> + */
> +enum {
> +	PIC32_PORT_A = 0,
> +	PIC32_PORT_B = 1,
> +	PIC32_PORT_C = 2,
> +	PIC32_PORT_D = 3,
> +	PIC32_PORT_E = 4,
> +	PIC32_PORT_F = 5,
> +	PIC32_PORT_G = 6,
> +	PIC32_PORT_H = 7,
> +	PIC32_PORT_J = 8, /* no PORT_I */
> +	PIC32_PORT_K = 9,
> +	PIC32_PINS_PER_PORT = 16,
> +};
> +
> +#define PIN_CONFIG_PIC32_DIGITAL	(PIN_CONFIG_END + 1)
> +#define PIN_CONFIG_PIC32_ANALOG		(PIN_CONFIG_END + 2)
> +
> +/* pin configuration descriptor */
> +struct pic32_pin_config {
> +	u16 port;	/* port number */
> +	u16 pin;	/* pin number in the port */
> +	u32 config;	/* one of PIN_CONFIG_* */
> +};
> +#define PIN_CONFIG(_prt, _pin, _cfg) \
> +	{.port = (_prt), .pin = (_pin), .config = (_cfg), }
> +
> +/* In PIC32 muxing is performed at pin-level through two
> + * different set of registers - one set for input functions,
> + * and other for output functions.
> + * Pin configuration is handled through port register.
> + */
> +/* Port control registers */
> +struct pic32_reg_port {
> +	struct pic32_reg_atomic ansel;
> +	struct pic32_reg_atomic tris;
> +	struct pic32_reg_atomic port;
> +	struct pic32_reg_atomic lat;
> +	struct pic32_reg_atomic odc;
> +	struct pic32_reg_atomic cnpu;
> +	struct pic32_reg_atomic cnpd;
> +	struct pic32_reg_atomic cncon;
> +	struct pic32_reg_atomic unused[8];
> +};
> +
> +/* Input function mux registers */
> +struct pic32_reg_in_mux {
> +	u32 unused0;
> +	u32 int1[4];
> +	u32 unused1;
> +	u32 t2ck[8];
> +	u32 ic1[9];
> +	u32 unused2;
> +	u32 ocfar;
> +	u32 unused3;
> +	u32 u1rx;
> +	u32 u1cts;
> +	u32 u2rx;
> +	u32 u2cts;
> +	u32 u3rx;
> +	u32 u3cts;
> +	u32 u4rx;
> +	u32 u4cts;
> +	u32 u5rx;
> +	u32 u5cts;
> +	u32 u6rx;
> +	u32 u6cts;
> +	u32 unused4;
> +	u32 sdi1;
> +	u32 ss1;
> +	u32 unused5;
> +	u32 sdi2;
> +	u32 ss2;
> +	u32 unused6;
> +	u32 sdi3;
> +	u32 ss3;
> +	u32 unused7;
> +	u32 sdi4;
> +	u32 ss4;
> +	u32 unused8;
> +	u32 sdi5;
> +	u32 ss5;
> +	u32 unused9;
> +	u32 sdi6;
> +	u32 ss6;
> +	u32 c1rx;
> +	u32 c2rx;
> +	u32 refclki1;
> +	u32 refclki2;
> +	u32 refclki3;
> +	u32 refclki4;
> +};
> +
> +/* output mux register offset */
> +#define PPS_OUT(__port, __pin) \
> +	(((__port) * PIC32_PINS_PER_PORT + (__pin)) << 2)
> +
> +
> +struct pic32_pinctrl_priv {
> +	struct pic32_reg_in_mux *mux_in; /* mux input function */
> +	struct pic32_reg_port *pinconf; /* pin configuration*/
> +	void __iomem *mux_out;	/* mux output function */
> +};
> +
> +enum {
> +	PERIPH_ID_UART1,
> +	PERIPH_ID_UART2,
> +	PERIPH_ID_ETH,
> +	PERIPH_ID_USB,
> +	PERIPH_ID_SDHCI,
> +	PERIPH_ID_I2C1,
> +	PERIPH_ID_I2C2,
> +	PERIPH_ID_SPI1,
> +	PERIPH_ID_SPI2,
> +	PERIPH_ID_SQI,
> +};
> +
> +static int pic32_pinconfig_one(struct pic32_pinctrl_priv *priv,
> +			       u32 port_nr, u32 pin, u32 param)
> +{
> +	struct pic32_reg_port *port;
> +
> +	port = &priv->pinconf[port_nr];
> +	switch (param) {
> +	case PIN_CONFIG_PIC32_DIGITAL:
> +		writel(BIT(pin), &port->ansel.clr);
> +		break;
> +	case PIN_CONFIG_PIC32_ANALOG:
> +		writel(BIT(pin), &port->ansel.set);
> +		break;
> +	case PIN_CONFIG_INPUT_ENABLE:
> +		writel(BIT(pin), &port->tris.set);
> +		break;
> +	case PIN_CONFIG_OUTPUT:
> +		writel(BIT(pin), &port->tris.clr);
> +		break;
> +	case PIN_CONFIG_BIAS_PULL_UP:
> +		writel(BIT(pin), &port->cnpu.set);
> +		break;
> +	case PIN_CONFIG_BIAS_PULL_DOWN:
> +		writel(BIT(pin), &port->cnpd.set);
> +		break;
> +	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
> +		writel(BIT(pin), &port->odc.set);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static int pic32_pinconfig_set(struct pic32_pinctrl_priv *priv,
> +			       const struct pic32_pin_config *list,
> int count)
> +{
> +	int i;
> +
> +	for (i = 0 ; i < count; i++)
> +		pic32_pinconfig_one(priv, list[i].port,
> +				    list[i].pin, list[i].config);
> +
> +	return 0;
> +}
> +
> +static void pic32_eth_pin_config(struct udevice *dev)
> +{
> +	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
> +	const struct pic32_pin_config configs[] = {
> +		/* EMDC - D11 */
> +		PIN_CONFIG(PIC32_PORT_D, 11,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_D, 11, PIN_CONFIG_OUTPUT),
> +		/* ETXEN */
> +		PIN_CONFIG(PIC32_PORT_D, 6,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_D, 6, PIN_CONFIG_OUTPUT),
> +		/* ECRSDV */
> +		PIN_CONFIG(PIC32_PORT_H, 13,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_H, 13,
> PIN_CONFIG_INPUT_ENABLE),
> +		/* ERXD0 */
> +		PIN_CONFIG(PIC32_PORT_H, 8,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_H, 8,
> PIN_CONFIG_INPUT_ENABLE),
> +		PIN_CONFIG(PIC32_PORT_H, 8,
> PIN_CONFIG_BIAS_PULL_DOWN),
> +		/* ERXD1 */
> +		PIN_CONFIG(PIC32_PORT_H, 5,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_H, 5,
> PIN_CONFIG_INPUT_ENABLE),
> +		PIN_CONFIG(PIC32_PORT_H, 5,
> PIN_CONFIG_BIAS_PULL_DOWN),
> +		/* EREFCLK */
> +		PIN_CONFIG(PIC32_PORT_J, 11,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_J, 11,
> PIN_CONFIG_INPUT_ENABLE),
> +		/* ETXD1 */
> +		PIN_CONFIG(PIC32_PORT_J, 9,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_J, 9, PIN_CONFIG_OUTPUT),
> +		/* ETXD0 */
> +		PIN_CONFIG(PIC32_PORT_J, 8,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_J, 8, PIN_CONFIG_OUTPUT),
> +		/* EMDIO */
> +		PIN_CONFIG(PIC32_PORT_J, 1,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_J, 1,
> PIN_CONFIG_INPUT_ENABLE),
> +		/* ERXERR */
> +		PIN_CONFIG(PIC32_PORT_F, 3,
> PIN_CONFIG_PIC32_DIGITAL),
> +		PIN_CONFIG(PIC32_PORT_F, 3,
> PIN_CONFIG_INPUT_ENABLE),
> +	};
> +
> +	pic32_pinconfig_set(priv, configs, ARRAY_SIZE(configs));
> +}
> +
> +static int pic32_pinctrl_request(struct udevice *dev, int func, int
> flags)
> +{
> +	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
> +
> +	switch (func) {
> +	case PERIPH_ID_UART2:
> +		/* PPS for U2 RX/TX */
> +		writel(0x02, priv->mux_out + PPS_OUT(PIC32_PORT_G,
> 9));
> +		writel(0x05, &priv->mux_in->u2rx); /* B0 */
> +		/* set digital mode */
> +		pic32_pinconfig_one(priv, PIC32_PORT_G, 9,
> +				    PIN_CONFIG_PIC32_DIGITAL);
> +		pic32_pinconfig_one(priv, PIC32_PORT_B, 0,
> +				    PIN_CONFIG_PIC32_DIGITAL);
> +		break;
> +	case PERIPH_ID_ETH:
> +		pic32_eth_pin_config(dev);
> +		break;
> +	default:
> +		debug("%s: unknown-unhandled case\n", __func__);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static int pic32_pinctrl_get_periph_id(struct udevice *dev,
> +				       struct udevice *periph)
> +{
> +	int ret;
> +	u32 cell[2];
> +
> +	ret = fdtdec_get_int_array(gd->fdt_blob, periph->of_offset,
> +				   "interrupts", cell,
> ARRAY_SIZE(cell));
> +	if (ret < 0)
> +		return -EINVAL;
> +
> +	/* interrupt number */
> +	switch (cell[0]) {
> +	case 112 ... 114:
> +		return PERIPH_ID_UART1;
> +	case 145 ... 147:
> +		return PERIPH_ID_UART2;
> +	case 109 ... 111:
> +		return PERIPH_ID_SPI1;
> +	case 142 ... 144:
> +		return PERIPH_ID_SPI2;
> +	case 115 ... 117:
> +		return PERIPH_ID_I2C1;
> +	case 148 ... 150:
> +		return PERIPH_ID_I2C2;
> +	case 132 ... 133:
> +		return PERIPH_ID_USB;
> +	case 169:
> +		return PERIPH_ID_SQI;
> +	case 191:
> +		return PERIPH_ID_SDHCI;
> +	case 153:
> +		return PERIPH_ID_ETH;
> +	default:
> +		break;
> +	}
> +
> +	return -ENOENT;
> +}
> +
> +static int pic32_pinctrl_set_state_simple(struct udevice *dev,
> +					  struct udevice *periph)
> +{
> +	int func;
> +
> +	debug("%s: periph %s\n", __func__, periph->name);
> +	func = pic32_pinctrl_get_periph_id(dev, periph);
> +	if (func < 0)
> +		return func;
> +	return pic32_pinctrl_request(dev, func, 0);
> +}
> +
> +static struct pinctrl_ops pic32_pinctrl_ops = {
> +	.set_state_simple	= pic32_pinctrl_set_state_simple,
> +	.request		= pic32_pinctrl_request,
> +	.get_periph_id		= pic32_pinctrl_get_periph_id,
> +};
> +
> +static int pic32_pinctrl_probe(struct udevice *dev)
> +{
> +	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
> +	struct fdt_resource res;
> +	void *fdt = (void *)gd->fdt_blob;
> +	int node = dev->of_offset;
> +	int ret;
> +
> +	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
> +				     "ppsin", &res);
> +	if (ret < 0) {
> +		printf("pinctrl: resource \"ppsin\" not found\n");
> +		return ret;
> +	}
> +	priv->mux_in = ioremap(res.start, fdt_resource_size(&res));
> +
> +	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
> +				     "ppsout", &res);
> +	if (ret < 0) {
> +		printf("pinctrl: resource \"ppsout\" not found\n");
> +		return ret;
> +	}
> +	priv->mux_out = ioremap(res.start, fdt_resource_size(&res));
> +
> +	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
> +				     "port", &res);
> +	if (ret < 0) {
> +		printf("pinctrl: resource \"port\" not found\n");
> +		return ret;
> +	}
> +	priv->pinconf = ioremap(res.start, fdt_resource_size(&res));
> +
> +	return 0;
> +}
> +
> +static int pic32_pinctrl_bind(struct udevice *dev)
> +{
> +	/* scan child GPIO banks */
> +	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset,
> false);
> +}
> +
> +static const struct udevice_id pic32_pinctrl_ids[] = {
> +	{ .compatible = "microchip,pic32mzda-pinctrl" },
> +	{ }
> +};
> +
> +U_BOOT_DRIVER(pinctrl_pic32) = {
> +	.name		= "pinctrl_pic32",
> +	.id		= UCLASS_PINCTRL,
> +	.of_match	= pic32_pinctrl_ids,
> +	.ops		= &pic32_pinctrl_ops,
> +	.probe		= pic32_pinctrl_probe,
> +	.bind		= pic32_pinctrl_bind,
> +	.priv_auto_alloc_size = sizeof(struct pic32_pinctrl_priv),
> +};
-- 
- Daniel

  reply	other threads:[~2016-01-13 13:42 UTC|newest]

Thread overview: 62+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-12 10:18 [U-Boot] [PATCH v3 00/14] Initial Microchip PIC32MZ[DA] Support Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 01/14] MIPS: initialize board_init_f() argument to zero Purna Chandra Mandal
2016-01-12 12:29   ` Daniel Schwierzeck
2016-01-14  5:29     ` Purna Chandra Mandal
2016-01-21 14:06       ` Daniel Schwierzeck
2016-01-12 10:18 ` [U-Boot] [PATCH v3 02/14] MIPS: initial infrastructure for Microchip PIC32 architecture Purna Chandra Mandal
2016-01-12 12:55   ` Daniel Schwierzeck
2016-01-13 14:56   ` Tom Rini
2016-01-12 10:18 ` [U-Boot] [PATCH v3 03/14] drivers: clk: Add clock driver for Microchip PIC32 Microcontroller Purna Chandra Mandal
2016-01-13 13:38   ` Daniel Schwierzeck
2016-01-14  5:34     ` Purna Chandra Mandal
2016-01-13 14:55   ` Tom Rini
2016-01-14  6:04     ` Purna Chandra Mandal
2016-01-14 12:30       ` Tom Rini
2016-01-12 10:18 ` [U-Boot] [PATCH v3 04/14] drivers: pinctrl: Add pinctrl driver for Microchip PIC32 Purna Chandra Mandal
2016-01-13 13:42   ` Daniel Schwierzeck [this message]
2016-01-13 14:55   ` Tom Rini
2016-01-13 20:10   ` Simon Glass
2016-01-12 10:18 ` [U-Boot] [PATCH v3 05/14] drivers: gpio: add driver for Microchip PIC32 GPIO controller Purna Chandra Mandal
2016-01-13 13:46   ` Daniel Schwierzeck
2016-01-13 14:08     ` Daniel Schwierzeck
2016-01-14  5:41       ` Purna Chandra Mandal
2016-01-13 14:55   ` Tom Rini
2016-01-13 20:10   ` Simon Glass
2016-01-14 10:15     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 06/14] drivers: serial: add driver for Microchip PIC32 UART controller Purna Chandra Mandal
2016-01-13 13:49   ` Daniel Schwierzeck
2016-01-13 14:03     ` Daniel Schwierzeck
2016-01-14  5:42       ` Purna Chandra Mandal
2016-01-13 14:55   ` Tom Rini
2016-01-13 20:09   ` Simon Glass
2016-01-14  6:14     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 07/14] drivers: ddr: Add DDR2 SDRAM controller driver for Microchip PIC32 Purna Chandra Mandal
2016-01-13 13:53   ` Daniel Schwierzeck
2016-01-13 14:55   ` Tom Rini
2016-01-13 20:09   ` Simon Glass
2016-01-12 10:18 ` [U-Boot] [PATCH v3 08/14] MIPS: Add support for Microchip PIC32MZ[DA] SoC family Purna Chandra Mandal
2016-01-13 14:49   ` Daniel Schwierzeck
2016-01-14  5:54     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 09/14] board: Add Microchip PIC32MZ[DA]-Starter-Kit board Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini
2016-01-14  6:40     ` Purna Chandra Mandal
2016-01-13 15:03   ` Daniel Schwierzeck
2016-01-14  8:40     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 10/14] drivers: mmc: add driver for Microchip PIC32 SDHCI controller Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini
2016-01-13 15:15   ` Daniel Schwierzeck
2016-01-14  9:18     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 11/14] board: add SDHCI support for PIC32MZDASK board Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini
2016-01-14  8:31     ` Purna Chandra Mandal
2016-01-12 10:18 ` [U-Boot] [PATCH v3 12/14] drivers: net: phy: add SMSC LAN8740 Phy support Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini
2016-01-13 15:19   ` Daniel Schwierzeck
2016-01-12 10:18 ` [U-Boot] [PATCH v3 13/14] drivers: net: Add ethernet driver for Microchip PIC32 Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini
2016-01-14 10:29     ` Purna Chandra Mandal
2016-01-13 15:37   ` Daniel Schwierzeck
2016-01-14 10:05     ` Purna Chandra Mandal
2016-01-14 14:01       ` Daniel Schwierzeck
2016-01-12 10:18 ` [U-Boot] [PATCH v3 14/14] board: Enable ethernet, tftpboot support to pic32mzdask board Purna Chandra Mandal
2016-01-13 14:56   ` Tom Rini

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