Hi Dmitry, From: Dmitry Torokhov [mailto:dmitry.torokhov@xxxxxxxxx] Sent: Thursday, July 07, 2011 8:07 PM > On Wed, Jul 06, 2011 at 06:13:33PM +0530, Patil, Rachna wrote: > > This patch adds support for TI's touchscreen > > controller for a 4/5/8 wire resistive panel > > that is directly fed to the ADC. > > > > This touchscreen controller will be part of > > an upcoming TI SoC and has been tested on > > an emulation platform. > > > > Signed-off-by: Patil, Rachna <rachna@xxxxxx> > > Looks mostly good, please find a few comments below. > > > --- > > drivers/input/touchscreen/Kconfig | 11 + > > drivers/input/touchscreen/Makefile | 1 + > > drivers/input/touchscreen/ti_tscadc.c | 417 > +++++++++++++++++++++++++++++++++ > > include/linux/input/ti_tsc.h | 7 + > > Maybe we should call it ti_tscadc.h to match the .c file? Ok. I will change this to ti_tscadc.h. > > > 4 files changed, 436 insertions(+), 0 deletions(-) > > create mode 100644 drivers/input/touchscreen/ti_tscadc.c > > create mode 100644 include/linux/input/ti_tsc.h > > > > diff --git a/drivers/input/touchscreen/Kconfig > b/drivers/input/touchscreen/Kconfig > > index 44589f5..9d5d3ba 100644 > > --- a/drivers/input/touchscreen/Kconfig > > +++ b/drivers/input/touchscreen/Kconfig > > @@ -704,4 +704,15 @@ config TOUCHSCREEN_TPS6507X > > To compile this driver as a module, choose M here: the > > module will be called tps6507x_ts. > > > > +config TOUCHSCREEN_TI_TSCADC > > + tristate "TI Touchscreen Interface" > > + help > > + Say Y here if you have 4/5/8 wire touchscreen controller > > + to be connected to the ADC controller on your TI SoC. > > + > > + If unsure, say N. > > + > > + To compile this driver as a module, choose M here: the > > + module will be called ti_tscadc. > > + > > endif > > diff --git a/drivers/input/touchscreen/Makefile > b/drivers/input/touchscreen/Makefile > > index 51b08b0..82d3098 100644 > > --- a/drivers/input/touchscreen/Makefile > > +++ b/drivers/input/touchscreen/Makefile > > @@ -58,3 +58,4 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) += > mainstone-wm97xx.o > > obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE) += zylonite-wm97xx.o > > obj-$(CONFIG_TOUCHSCREEN_W90X900) += w90p910_ts.o > > obj-$(CONFIG_TOUCHSCREEN_TPS6507X) += tps6507x-ts.o > > +obj-$(CONFIG_TOUCHSCREEN_TI_TSCADC) += ti_tscadc.o > > Please try keeping Kconfig and Makefile sorted alphabetically. I will rearrange this. > > > diff --git a/drivers/input/touchscreen/ti_tscadc.c > b/drivers/input/touchscreen/ti_tscadc.c > > new file mode 100644 > > index 0000000..0308f71 > > --- /dev/null > > +++ b/drivers/input/touchscreen/ti_tscadc.c > > @@ -0,0 +1,417 @@ > > +/* > > + * TI Touch Screen driver > > + * > > + * Copyright (C) 2011 Texas Instruments Incorporated - > http://www.ti.com/ > > + * > > + * 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 version 2. > > + * > > + * This program is distributed "as is" WITHOUT ANY WARRANTY of any > > + * kind, whether express or implied; without even the implied warranty > > + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + */ > > + > > + > > +#include <linux/init.h> > > +#include <linux/kernel.h> > > +#include <linux/err.h> > > +#include <linux/module.h> > > +#include <linux/input.h> > > +#include <linux/slab.h> > > +#include <linux/interrupt.h> > > +#include <linux/clk.h> > > +#include <linux/platform_device.h> > > +#include <linux/io.h> > > +#include <linux/input/ti_tsc.h> > > + > > +#define TSCADC_REG_IRQEOI 0x020 > > +#define TSCADC_REG_IRQSTATUS 0x028 > > +#define TSCADC_REG_IRQENABLE 0x02C > > +#define TSCADC_REG_IRQWAKEUP 0x034 > > +#define TSCADC_REG_CTRL 0x040 > > +#define TSCADC_REG_ADCFSM 0x044 > > +#define TSCADC_REG_CLKDIV 0x04C > > +#define TSCADC_REG_SE 0x054 > > +#define TSCADC_REG_IDLECONFIG 0x058 > > +#define TSCADC_REG_CHARGECONFIG 0x05C > > +#define TSCADC_REG_STEPCONFIG1 0x064 > > +#define TSCADC_REG_STEPDELAY1 0x068 > > +#define TSCADC_REG_STEPCONFIG2 0x06C > > +#define TSCADC_REG_STEPDELAY2 0x070 > > +#define TSCADC_REG_FIFO0 0x100 > > + > > +/* Register Bitfields */ > > +#define TSCADC_IRQWKUP_ENB BIT(0) > > +#define TSCADC_STPENB_STEPENB (7 << 0) > > +#define TSCADC_IRQENB_IRQHWPEN BIT(10) > > +#define TSCADC_IRQENB_IRQEOS BIT(1) > > +#define TSCADC_IRQENB_FIFO_OVERFLOW BIT(3) > > +#define TSCADC_IRQENB_PENUP BIT(9) > > +#define TSCADC_STEPCONFIG_MODE_HWSYNC 0x3 > > +#define TSCADC_STEPCONFIG_2SAMPLES_AVG BIT(2) > > +#define TSCADC_STEPCONFIG_XPP BIT(5) > > +#define TSCADC_STEPCONFIG_XNN BIT(6) > > +#define TSCADC_STEPCONFIG_YPP BIT(7) > > +#define TSCADC_STEPCONFIG_YNN BIT(8) > > +#define TSCADC_STEPCONFIG_XNP BIT(9) > > +#define TSCADC_STEPCONFIG_YPN BIT(10) > > +#define TSCADC_STEPCONFIG_RFP_X (1 << 12) > > +#define TSCADC_STEPCONFIG_RFP_4_Y (1 << 13) > > +#define TSCADC_STEPCONFIG_RFP_5_Y (1 << 12) > > +#define TSCADC_STEPCONFIG_RFP_8_Y (1 << 13) > > +#define TSCADC_STEPCONFIG_INM (1 << 18) > > +#define TSCADC_STEPCONFIG_INP_4 (1 << 20) > > +#define TSCADC_STEPCONFIG_INP_5 (1 << 21) > > +#define TSCADC_STEPCONFIG_INP_8_X (3 << 20) > > +#define TSCADC_STEPCONFIG_INP_8_Y (1 << 21) > > +#define TSCADC_STEPCONFIG_RFM_4_X (1 << 23) > > +#define TSCADC_STEPCONFIG_RFM_5_X (1 << 24) > > +#define TSCADC_STEPCONFIG_RFM_8_X (1 << 23) > > +#define TSCADC_STEPCONFIG_RFM_Y (1 << 24) > > +#define TSCADC_STEPCONFIG_OPENDLY (0xf << 0) > > +#define TSCADC_STEPCONFIG_SAMPLEDLY BIT(25) > > +#define TSCADC_STEPCHARGE_INM BIT(18) > > +#define TSCADC_STEPCHARGE_RFM (3 << 23) > > +#define TSCADC_CNTRLREG_TSCSSENB BIT(0) > > +#define TSCADC_CNTRLREG_STEPID BIT(1) > > +#define TSCADC_CNTRLREG_STEPCONFIGWRT BIT(2) > > +#define TSCADC_CNTRLREG_TSCENB BIT(7) > > +#define TSCADC_CNTRLREG_4WIRE (0x1 << 5) > > +#define TSCADC_CNTRLREG_5WIRE (0x1 << 6) > > +#define TSCADC_CNTRLREG_8WIRE (0x3 << 5) > > +#define TSCADC_ADCFSM_STEPID 0x10 > > +#define TSCADC_ADCFSM_FSM BIT(5) > > + > > +#define ADC_CLK 3000000 > > + > > +#define MAX_12BIT ((1 << 12) - 1) > > + > > +struct tscadc { > > + struct input_dev *input; > > + int wires; > > + struct clk *clk; > > + int irq; > > + void __iomem *tsc_base; > > +}; > > + > > +static inline unsigned int tscadc_readl(struct tscadc *ts, unsigned int > reg) > > Drop the 'inline', let compiler figure out what needs to be inlined. Ok. > > > +{ > > + return readl(ts->tsc_base + reg); > > +} > > + > > +static inline void tscadc_writel(struct tscadc *tsc, unsigned int reg, > > + unsigned int val) > > +{ > > + writel(val, tsc->tsc_base + reg); > > +} > > + > > +void tsc_idle_config(struct tscadc *ts_config) > > Should be static. Ok. > > > +{ > > + /* Idle mode touch screen config */ > > + unsigned int idleconfig; > > + > > + idleconfig = TSCADC_STEPCONFIG_YNN | > > + TSCADC_STEPCONFIG_RFP_X | > > + TSCADC_STEPCONFIG_INM ; > > + > > + if (ts_config->wires == 4) { > > switch (ts_config->wires) { > case 4: > ... > } Will add switch cases accordingly through out the code. > > > + idleconfig |= TSCADC_STEPCONFIG_INP_4 | > > + TSCADC_STEPCONFIG_RFM_4_X; > > + > > + } else if (ts_config->wires == 5) { > > + idleconfig |= TSCADC_STEPCONFIG_INP_5 | > > + TSCADC_STEPCONFIG_RFM_5_X; > > + > > + } else { > > + idleconfig |= TSCADC_STEPCONFIG_INP_4 | > > + TSCADC_STEPCONFIG_RFM_8_X; > > + } > > + tscadc_writel(ts_config, TSCADC_REG_IDLECONFIG, idleconfig); > > +} > > + > > +static irqreturn_t tscadc_interrupt(int irq, void *dev) > > +{ > > + struct tscadc *ts_dev = (struct tscadc *)dev; > > + struct input_dev *input_dev = ts_dev->input; > > + unsigned int status, store, cntrlreg, irqclr = 0; > > + int absx, absy; > > + int charge, fsm; > > + > > + status = tscadc_readl(ts_dev, TSCADC_REG_IRQSTATUS); > > + tscadc_writel(ts_dev, TSCADC_REG_SE, 0x0); > > + > > + /* Pen touch event */ > > + if (status & TSCADC_IRQENB_IRQHWPEN) > > + irqclr = status & TSCADC_IRQENB_IRQHWPEN; > > + > > + if (status & TSCADC_IRQENB_PENUP) { > > + /* Pen up event */ > > + charge = TSCADC_STEPCHARGE_INM | TSCADC_STEPCHARGE_RFM; > > + tscadc_writel(ts_dev, TSCADC_REG_CHARGECONFIG, charge); > > + input_report_key(input_dev, BTN_TOUCH, 0); > > input_sync(input_dev); Will add this. > > > + tsc_idle_config(ts_dev); > > + irqclr |= status & TSCADC_IRQENB_PENUP; > > You already know that TSCADC_IRQENB_PENUP in status is set, so can do > > irqclr |= TSCADC_IRQENB_PENUP; > > But you do it several times. If you define a bitmask mask you can do > > irqclr = status & TSCADC_IRQENB_MASK; > > once before writing it back to the device. Will change it to irqclr |= TSCADC_IRQENB_PENUP; > > > + > > + } > > + if (status & TSCADC_IRQENB_IRQEOS) { > > + /* ADC is done with sampling, ready to read the data */ > > + absx = tscadc_readl(ts_dev, TSCADC_REG_FIFO0); > > + absy = tscadc_readl(ts_dev, TSCADC_REG_FIFO0); > > + > > + input_report_abs(input_dev, ABS_X, absx); > > + input_report_abs(input_dev, ABS_Y, absy); > > + input_report_key(input_dev, BTN_TOUCH, 1); > > input_sync(input_dev); I will add this. > > > + > > + irqclr |= status & TSCADC_IRQENB_IRQEOS; > > + > > + } > > + if (status & TSCADC_IRQENB_FIFO_OVERFLOW) { > > + /* FIFO overflow condition */ > > + cntrlreg = tscadc_readl(ts_dev, TSCADC_REG_CTRL); > > + cntrlreg &= ~TSCADC_CNTRLREG_TSCSSENB; > > + tscadc_writel(ts_dev, TSCADC_REG_CTRL, cntrlreg); > > + > > + irqclr |= status & TSCADC_IRQENB_FIFO_OVERFLOW; > > + } > > + > > + tscadc_writel(ts_dev, TSCADC_REG_IRQSTATUS, irqclr); > > + fsm = tscadc_readl(ts_dev, TSCADC_REG_ADCFSM); > > + if ((fsm & TSCADC_ADCFSM_FSM) && > > + (fsm & TSCADC_ADCFSM_STEPID)) { > > + store = tscadc_readl(ts_dev, TSCADC_REG_CTRL); > > + store |= TSCADC_CNTRLREG_TSCSSENB; > > + tscadc_writel(ts_dev, TSCADC_REG_CTRL, store); > > + } > > + > > + /* check pending interrupts */ > > + tscadc_writel(ts_dev, TSCADC_REG_IRQEOI, 0x0); > > + > > + tscadc_writel(ts_dev, TSCADC_REG_SE, TSCADC_STPENB_STEPENB); > > + return IRQ_HANDLED; > > +} > > + > > +/* > > +* The functions for inserting/removing driver as a module. > > +*/ > > + > > +static int __devinit tscadc_probe(struct platform_device *pdev) > > +{ > > + struct tscadc *ts_dev; > > + struct input_dev *input_dev; > > + int err; > > + int clk_value; > > + int clock_rate, ctrl, irqenable; > > + struct tsc_data *pdata = pdev->dev.platform_data; > > + struct resource *res; > > + int stepconfig1, stepconfig2, delay; > > + > > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + if (!res) { > > + dev_err(&pdev->dev, "no memory resource defined.\n"); > > + return -ENXIO; > > -EINVAL? We do expect the device to be set up properly. Agree. > > > + } > > + > > + /* Allocate memory for device */ > > + ts_dev = kzalloc(sizeof(struct tscadc), GFP_KERNEL); > > + if (!ts_dev) { > > + dev_err(&pdev->dev, "failed to allocate memory.\n"); > > + return -ENOMEM; > > + } > > + > > + input_dev = input_allocate_device(); > > + if (!input_dev) { > > + dev_err(&pdev->dev, "failed to allocate input device.\n"); > > + err = -EBUSY; > > -ENOMEM instead of -EBUSY. Ok. > > > + goto err_free_mem; > > + } > > + ts_dev->input = input_dev; > > + > > + ts_dev->irq = platform_get_irq(pdev, 0); > > + if (ts_dev->irq < 0) { > > + dev_err(&pdev->dev, "no irq ID is specified.\n"); > > Why don't you check if you have IRQ before allocating memory, like you > did with the IO? Will rearrange. > > > + err = -ENODEV; > > Probably should be -EINVAL. Ok. > > > + goto err_free_dev; > > + } > > + > > + ts_dev->tsc_base = ioremap(res->start, resource_size(res)); > > + if (!(ts_dev->tsc_base)) { > > Drop extra parens. > Ok > > + dev_err(&pdev->dev, "failed to map registers.\n"); > > + err = -ENOMEM; > > + goto err_release_mem; > > + } > > + > > + err = request_irq(ts_dev->irq, tscadc_interrupt, IRQF_DISABLED, > > + pdev->dev.driver->name, ts_dev); > > Please indent this line more. > Ok. > > + if (err) { > > + dev_err(&pdev->dev, "failed to allocate irq.\n"); > > + goto err_unmap_regs; > > + } > > + > > + ts_dev->clk = clk_get(&pdev->dev, "tsc_clk"); > > + if (IS_ERR(ts_dev->clk)) { > > + dev_err(&pdev->dev, "failed to get ts_clk\n"); > > + err = PTR_ERR(ts_dev->clk); > > + goto err_free_irq; > > + } > > + clk_enable(ts_dev->clk); > > + > > + clock_rate = clk_get_rate(ts_dev->clk); > > + clk_value = clock_rate / ADC_CLK; > > + if (clk_value < 7) { > > + dev_err(&pdev->dev, "clock input less than min clock > requirement\n"); > > + goto err_fail; > > + } > > + /* TSCADC_CLKDIV needs to be configured to the value minus 1 */ > > + clk_value = clk_value - 1; > > + tscadc_writel(ts_dev, TSCADC_REG_CLKDIV, clk_value); > > + > > + /* Enable wake-up of the SoC using touchscreen */ > > + tscadc_writel(ts_dev, TSCADC_REG_IRQWAKEUP, TSCADC_IRQWKUP_ENB); > > + > > + ts_dev->wires = pdata->wires; > > + > > + /* Set the control register bits */ > > + ctrl = TSCADC_CNTRLREG_STEPCONFIGWRT | > > + TSCADC_CNTRLREG_TSCENB | > > + TSCADC_CNTRLREG_STEPID; > > + if (ts_dev->wires == 4) > > switch() > > > + ctrl |= TSCADC_CNTRLREG_4WIRE; > > + else if (ts_dev->wires == 5) > > + ctrl |= TSCADC_CNTRLREG_5WIRE; > > + else > > + ctrl |= TSCADC_CNTRLREG_8WIRE; > > + tscadc_writel(ts_dev, TSCADC_REG_CTRL, ctrl); > > + tscadc_readl(ts_dev, TSCADC_REG_CTRL); > > + > > + /* Set register bits for Idel Config Mode */ > > + tsc_idle_config(ts_dev); > > + > > + /* IRQ Enable */ > > + irqenable = TSCADC_IRQENB_IRQHWPEN | > > + TSCADC_IRQENB_IRQEOS | > > + TSCADC_IRQENB_PENUP | TSCADC_IRQENB_FIFO_OVERFLOW; > > + tscadc_writel(ts_dev, TSCADC_REG_IRQENABLE, irqenable); > > + tscadc_readl(ts_dev, TSCADC_REG_IRQENABLE); > > + > > + /* Configure the Step registers */ > > + stepconfig1 = TSCADC_STEPCONFIG_MODE_HWSYNC | > > + TSCADC_STEPCONFIG_2SAMPLES_AVG | TSCADC_STEPCONFIG_XPP | > > + TSCADC_STEPCONFIG_XNN | TSCADC_STEPCONFIG_INM | > > + TSCADC_STEPCONFIG_RFP_X; > > + > > + stepconfig2 = TSCADC_STEPCONFIG_MODE_HWSYNC | > > + TSCADC_STEPCONFIG_2SAMPLES_AVG | TSCADC_STEPCONFIG_YNN | > > + TSCADC_STEPCONFIG_INM | TSCADC_STEPCONFIG_RFM_Y; > > + if (ts_dev->wires == 4) { > > switch(). > > > + stepconfig1 |= TSCADC_STEPCONFIG_INP_4 | > > + TSCADC_STEPCONFIG_RFM_4_X; > > + > > + stepconfig2 |= TSCADC_STEPCONFIG_YPP | > > + TSCADC_STEPCONFIG_RFP_4_Y; > > + > > + } else if (ts_dev->wires == 5) { > > + stepconfig1 |= TSCADC_STEPCONFIG_YPP | > > + TSCADC_STEPCONFIG_YNN | > > + TSCADC_STEPCONFIG_INP_5 | > > + TSCADC_STEPCONFIG_RFM_5_X; > > + > > + stepconfig2 |= TSCADC_STEPCONFIG_XPP | > > + TSCADC_STEPCONFIG_XNP | > > + TSCADC_STEPCONFIG_YPN | > > + TSCADC_STEPCONFIG_RFP_5_Y | > > + TSCADC_STEPCONFIG_INP_5; > > + } else{ > > + stepconfig1 |= TSCADC_STEPCONFIG_INP_8_X | > > + TSCADC_STEPCONFIG_RFM_8_X; > > + > > + stepconfig2 |= TSCADC_STEPCONFIG_YPP | > > + TSCADC_STEPCONFIG_RFP_8_Y | > > + TSCADC_STEPCONFIG_INP_8_Y; > > + } > > + delay = TSCADC_STEPCONFIG_OPENDLY | TSCADC_STEPCONFIG_SAMPLEDLY; > > + > > + tscadc_writel(ts_dev, TSCADC_REG_STEPCONFIG1, stepconfig1); > > + tscadc_writel(ts_dev, TSCADC_REG_STEPDELAY1, delay); > > + tscadc_writel(ts_dev, TSCADC_REG_STEPCONFIG2, stepconfig2); > > + tscadc_writel(ts_dev, TSCADC_REG_STEPDELAY2, delay); > > + > > + tscadc_writel(ts_dev, TSCADC_REG_SE, TSCADC_STPENB_STEPENB); > > + > > + ctrl |= TSCADC_CNTRLREG_TSCSSENB; > > + tscadc_writel(ts_dev, TSCADC_REG_CTRL, ctrl); > > + > > This chip programming could be split into a separate function. > Agree. I will add a function to do the chip programming. > > + input_dev->name = "ti-tsc-adcc"; > > + input_dev->dev.parent = &pdev->dev; > > input_dev->id.bustype = BUS_HOST? Since this touchscreen is on the SoC, I omitted this. > > > + > > + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); > > + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); > > + > > + input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0); > > + input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0); > > + > > + /* register to the input system */ > > + err = input_register_device(input_dev); > > + if (err) > > + goto err_fail; > > + > > + return 0; > > + > > +err_fail: > > + clk_disable(ts_dev->clk); > > + clk_put(ts_dev->clk); > > +err_free_irq: > > + free_irq(ts_dev->irq, ts_dev); > > +err_unmap_regs: > > + iounmap(ts_dev->tsc_base); > > +err_release_mem: > > + release_mem_region(res->start, resource_size(res)); > > +err_free_dev: > > + input_free_device(ts_dev->input); > > +err_free_mem: > > + kfree(ts_dev); > > + return err; > > +} > > + > > +static int __devexit tscadc_remove(struct platform_device *pdev) > > +{ > > + struct tscadc *ts_dev = dev_get_drvdata(&pdev->dev); > > + struct resource *res; > > + > > + free_irq(ts_dev->irq, ts_dev); > > + > > + input_unregister_device(ts_dev->input); > > + > > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + iounmap(ts_dev->tsc_base); > > + release_mem_region(res->start, resource_size(res)); > > + > > + clk_disable(ts_dev->clk); > > + clk_put(ts_dev->clk); > > + > > + kfree(ts_dev); > > + > > + return 0; > > +} > > + > > +static struct platform_driver ti_tsc_driver = { > > + .probe = tscadc_probe, > > + .remove = __devexit_p(tscadc_remove), > > + .driver = { > > + .name = "tsc", > > .owner = THIS_MODULE; > > No power management needed? > For now this is not handling. I will add this in patches that will be submitted in days to come. > > + }, > > +}; > > + > > +static int __init ti_tsc_init(void) > > +{ > > + return platform_driver_register(&ti_tsc_driver); > > +} > > + > > +static void __exit ti_tsc_exit(void) > > +{ > > + platform_driver_unregister(&ti_tsc_driver); > > +} > > + > > +module_init(ti_tsc_init); > > +module_exit(ti_tsc_exit); > > diff --git a/include/linux/input/ti_tsc.h b/include/linux/input/ti_tsc.h > > new file mode 100644 > > index 0000000..f499773 > > --- /dev/null > > +++ b/include/linux/input/ti_tsc.h > > @@ -0,0 +1,7 @@ > > +/* touch screen wire configuration */ > > + > > +struct tsc_data { > > + int wires; /* Wires refer to application modes > > + i.e. 4/5/8 wire touchscreen support > > + on the platform */ > > +}; > > -- > > 1.6.2.4 > > > > Thanks. > > -- > Dmitry Thanks & Regards, Rachna. -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html