From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265201AbUG2SWW (ORCPT ); Thu, 29 Jul 2004 14:22:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267754AbUG2O4c (ORCPT ); Thu, 29 Jul 2004 10:56:32 -0400 Received: from styx.suse.cz ([82.119.242.94]:62101 "EHLO shadow.ucw.cz") by vger.kernel.org with ESMTP id S264774AbUG2OIH convert rfc822-to-8bit (ORCPT ); Thu, 29 Jul 2004 10:08:07 -0400 To: torvalds@osdl.org, vojtech@suse.cz, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=US-ASCII Subject: [PATCH 4/47] Ensure exclusive access to variables in atkbd.c Content-Transfer-Encoding: 7BIT Date: Thu, 29 Jul 2004 16:09:54 +0200 X-Mailer: gregkh_patchbomb_levon_offspring In-Reply-To: <1091110194564@twilight.ucw.cz> From: Vojtech Pavlik Message-Id: <10911101944159@twilight.ucw.cz> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org You can pull this changeset from: bk://kernel.bkbits.net/vojtech/input =================================================================== ChangeSet@1.1722.54.2, 2004-05-30 16:57:22+02:00, vojtech@suse.cz input: Make atomicity and exclusive access to variables explicit in atkbd.c, using bitops. Signed-off-by: Vojtech Pavlik atkbd.c | 133 ++++++++++++++++++++++++++++++++++++++++++---------------------- 1 files changed, 89 insertions(+), 44 deletions(-) =================================================================== diff -Nru a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c --- a/drivers/input/keyboard/atkbd.c Thu Jul 29 14:42:14 2004 +++ b/drivers/input/keyboard/atkbd.c Thu Jul 29 14:42:14 2004 @@ -164,34 +164,48 @@ { ATKBD_SCR_CLICK, 0x60 }, }; +#define ATKBD_FLAG_ACK 0 /* Waiting for ACK/NAK */ +#define ATKBD_FLAG_CMD 1 /* Waiting for command to finish */ +#define ATKBD_FLAG_CMD1 2 /* First byte of command response */ +#define ATKBD_FLAG_ID 3 /* First byte is not keyboard ID */ +#define ATKBD_FLAG_ENABLED 4 /* Waining for init to finish */ + /* * The atkbd control structure */ struct atkbd { - unsigned char keycode[512]; - struct input_dev dev; - struct serio *serio; + /* Written only during init */ char name[64]; char phys[32]; - unsigned short id; + struct serio *serio; + struct input_dev dev; + unsigned char set; - unsigned int translated:1; - unsigned int extra:1; - unsigned int write:1; + unsigned short id; + unsigned char keycode[512]; + unsigned char translated; + unsigned char extra; + unsigned char write; + + /* Protected by FLAG_ACK */ + unsigned char nak; + /* Protected by FLAG_CMD */ unsigned char cmdbuf[4]; unsigned char cmdcnt; - volatile signed char ack; - unsigned char emul; - unsigned int resend:1; - unsigned int release:1; - unsigned int bat_xl:1; - unsigned int enabled:1; + /* Accessed only from interrupt */ + unsigned char emul; + unsigned char resend; + unsigned char release; + unsigned char bat_xl; unsigned int last; unsigned long time; + + /* Flags */ + unsigned long flags; }; static void atkbd_report_key(struct input_dev *dev, struct pt_regs *regs, int code, int value) @@ -224,7 +238,7 @@ #if !defined(__i386__) && !defined (__x86_64__) if ((flags & (SERIO_FRAME | SERIO_PARITY)) && (~flags & SERIO_TIMEOUT) && !atkbd->resend && atkbd->write) { - printk("atkbd.c: frame/parity error: %02x\n", flags); + printk(KERN_WARNING "atkbd.c: frame/parity error: %02x\n", flags); serio_write(serio, ATKBD_CMD_RESEND); atkbd->resend = 1; goto out; @@ -234,22 +248,36 @@ atkbd->resend = 0; #endif - if (!atkbd->ack) + if (test_bit(ATKBD_FLAG_ACK, &atkbd->flags)) switch (code) { case ATKBD_RET_ACK: - atkbd->ack = 1; + atkbd->nak = 0; + clear_bit(ATKBD_FLAG_ACK, &atkbd->flags); goto out; case ATKBD_RET_NAK: - atkbd->ack = -1; + atkbd->nak = 1; + clear_bit(ATKBD_FLAG_ACK, &atkbd->flags); goto out; } - if (atkbd->cmdcnt) { - atkbd->cmdbuf[--atkbd->cmdcnt] = code; + if (test_bit(ATKBD_FLAG_CMD, &atkbd->flags)) { + + atkbd->cmdcnt--; + atkbd->cmdbuf[atkbd->cmdcnt] = code; + + if (atkbd->cmdcnt == 1) { + if (code != 0xab && code != 0xac) + clear_bit(ATKBD_FLAG_ID, &atkbd->flags); + clear_bit(ATKBD_FLAG_CMD1, &atkbd->flags); + } + + if (!atkbd->cmdcnt) + clear_bit(ATKBD_FLAG_CMD, &atkbd->flags); + goto out; } - if (!atkbd->enabled) + if (!test_bit(ATKBD_FLAG_ENABLED, &atkbd->flags)) goto out; if (atkbd->translated) { @@ -270,6 +298,7 @@ switch (code) { case ATKBD_RET_BAT: + clear_bit(ATKBD_FLAG_ENABLED, &atkbd->flags); serio_rescan(atkbd->serio); goto out; case ATKBD_RET_EMUL0: @@ -376,18 +405,19 @@ static int atkbd_sendbyte(struct atkbd *atkbd, unsigned char byte) { - int timeout = 20000; /* 200 msec */ - atkbd->ack = 0; + int timeout = 200000; /* 200 msec */ #ifdef ATKBD_DEBUG printk(KERN_DEBUG "atkbd.c: Sent: %02x\n", byte); #endif + + set_bit(ATKBD_FLAG_ACK, &atkbd->flags); if (serio_write(atkbd->serio, byte)) return -1; + while (test_bit(ATKBD_FLAG_ACK, &atkbd->flags) && timeout--) udelay(1); + clear_bit(ATKBD_FLAG_ACK, &atkbd->flags); - while (!atkbd->ack && timeout--) udelay(10); - - return -(atkbd->ack <= 0); + return -atkbd->nak; } /* @@ -411,40 +441,52 @@ for (i = 0; i < receive; i++) atkbd->cmdbuf[(receive - 1) - i] = param[i]; + if (receive) { + set_bit(ATKBD_FLAG_CMD, &atkbd->flags); + set_bit(ATKBD_FLAG_CMD1, &atkbd->flags); + set_bit(ATKBD_FLAG_ID, &atkbd->flags); + } + if (command & 0xff) - if (atkbd_sendbyte(atkbd, command & 0xff)) - return (atkbd->cmdcnt = 0) - 1; + if (atkbd_sendbyte(atkbd, command & 0xff)) { + clear_bit(ATKBD_FLAG_CMD, &atkbd->flags); + return -1; + } for (i = 0; i < send; i++) - if (atkbd_sendbyte(atkbd, param[i])) - return (atkbd->cmdcnt = 0) - 1; + if (atkbd_sendbyte(atkbd, param[i])) { + clear_bit(ATKBD_FLAG_CMD, &atkbd->flags); + return -1; + } - while (atkbd->cmdcnt && timeout--) { + while (test_bit(ATKBD_FLAG_CMD, &atkbd->flags) && timeout--) { - if (atkbd->cmdcnt == 1 && - command == ATKBD_CMD_RESET_BAT && timeout > 100000) - timeout = 100000; - - if (atkbd->cmdcnt == 1 && command == ATKBD_CMD_GETID && - atkbd->cmdbuf[1] != 0xab && atkbd->cmdbuf[1] != 0xac) { - atkbd->cmdcnt = 0; - break; + if (!test_bit(ATKBD_FLAG_CMD1, &atkbd->flags)) { + + if (command == ATKBD_CMD_RESET_BAT && timeout > 100000) + timeout = 100000; + + if (command == ATKBD_CMD_GETID && !test_bit(ATKBD_FLAG_ID, &atkbd->flags)) { + clear_bit(ATKBD_FLAG_CMD, &atkbd->flags); + atkbd->cmdcnt = 0; + break; + } } udelay(1); } + clear_bit(ATKBD_FLAG_CMD, &atkbd->flags); + if (param) for (i = 0; i < receive; i++) param[i] = atkbd->cmdbuf[(receive - 1) - i]; if (command == ATKBD_CMD_RESET_BAT && atkbd->cmdcnt == 1) - atkbd->cmdcnt = 0; + return 0; - if (atkbd->cmdcnt) { - atkbd->cmdcnt = 0; + if (atkbd->cmdcnt) return -1; - } return 0; } @@ -672,6 +714,7 @@ static void atkbd_disconnect(struct serio *serio) { struct atkbd *atkbd = serio->private; + clear_bit(ATKBD_FLAG_ENABLED, &atkbd->flags); input_unregister_device(&atkbd->dev); serio_close(serio); kfree(atkbd); @@ -719,7 +762,6 @@ atkbd->dev.rep[REP_PERIOD] = 33; } - atkbd->ack = 1; atkbd->serio = serio; init_input_dev(&atkbd->dev); @@ -754,7 +796,6 @@ atkbd->id = 0xab00; } - atkbd->enabled = 1; if (atkbd->extra) { atkbd->dev.ledbit[0] |= BIT(LED_COMPOSE) | BIT(LED_SUSPEND) | BIT(LED_SLEEP) | BIT(LED_MUTE) | BIT(LED_MISC); @@ -797,6 +838,8 @@ input_register_device(&atkbd->dev); + set_bit(ATKBD_FLAG_ENABLED, &atkbd->flags); + printk(KERN_INFO "input: %s on %s\n", atkbd->name, serio->phys); } @@ -831,6 +874,8 @@ if (atkbd_command(atkbd, param, ATKBD_CMD_SETLEDS)) return -1; } + + set_bit(ATKBD_FLAG_ENABLED, &atkbd->flags); return 0; }