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put_tty_driver() is an alias for tty_driver_kref_put(). There is no need for two exported identical functions, therefore switch all users of old put_tty_driver() to new tty_driver_kref_put() and remove the former for good. Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com> Cc: Jens Taprogge <jens.taprogge@taprogge.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Scott Branden <scott.branden@broadcom.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Lin <dtwlin@gmail.com> Cc: Johan Hovold <johan@kernel.org> Cc: Alex Elder <elder@kernel.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Oliver Neukum <oneukum@suse.com> Cc: Felipe Balbi <balbi@kernel.org> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Acked-by: Alex Elder <elder@linaro.org> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: David Sterba <dsterba@suse.com> Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210723074317.32690-8-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1081 lines
22 KiB
C
1081 lines
22 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* vcc.c: sun4v virtual channel concentrator
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*
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* Copyright (C) 2017 Oracle. All rights reserved.
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*/
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#include <linux/delay.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/sysfs.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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#include <asm/vio.h>
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#include <asm/ldc.h>
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MODULE_DESCRIPTION("Sun LDOM virtual console concentrator driver");
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MODULE_LICENSE("GPL");
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MODULE_VERSION("1.1");
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struct vcc_port {
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struct vio_driver_state vio;
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spinlock_t lock;
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char *domain;
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struct tty_struct *tty; /* only populated while dev is open */
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unsigned long index; /* index into the vcc_table */
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u64 refcnt;
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bool excl_locked;
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bool removed;
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/* This buffer is required to support the tty write_room interface
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* and guarantee that any characters that the driver accepts will
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* be eventually sent, either immediately or later.
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*/
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int chars_in_buffer;
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struct vio_vcc buffer;
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struct timer_list rx_timer;
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struct timer_list tx_timer;
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};
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/* Microseconds that thread will delay waiting for a vcc port ref */
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#define VCC_REF_DELAY 100
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#define VCC_MAX_PORTS 1024
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#define VCC_MINOR_START 0 /* must be zero */
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#define VCC_BUFF_LEN VIO_VCC_MTU_SIZE
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#define VCC_CTL_BREAK -1
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#define VCC_CTL_HUP -2
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static struct tty_driver *vcc_tty_driver;
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static struct vcc_port *vcc_table[VCC_MAX_PORTS];
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static DEFINE_SPINLOCK(vcc_table_lock);
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static unsigned int vcc_dbg;
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static unsigned int vcc_dbg_ldc;
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static unsigned int vcc_dbg_vio;
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module_param(vcc_dbg, uint, 0664);
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module_param(vcc_dbg_ldc, uint, 0664);
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module_param(vcc_dbg_vio, uint, 0664);
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#define VCC_DBG_DRV 0x1
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#define VCC_DBG_LDC 0x2
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#define VCC_DBG_PKT 0x4
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#define vccdbg(f, a...) \
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do { \
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if (vcc_dbg & VCC_DBG_DRV) \
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pr_info(f, ## a); \
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} while (0) \
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#define vccdbgl(l) \
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do { \
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if (vcc_dbg & VCC_DBG_LDC) \
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ldc_print(l); \
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} while (0) \
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#define vccdbgp(pkt) \
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do { \
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if (vcc_dbg & VCC_DBG_PKT) { \
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int i; \
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for (i = 0; i < pkt.tag.stype; i++) \
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pr_info("[%c]", pkt.data[i]); \
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} \
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} while (0) \
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/* Note: Be careful when adding flags to this line discipline. Don't
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* add anything that will cause echoing or we'll go into recursive
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* loop echoing chars back and forth with the console drivers.
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*/
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static const struct ktermios vcc_tty_termios = {
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.c_iflag = IGNBRK | IGNPAR,
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.c_oflag = OPOST,
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.c_cflag = B38400 | CS8 | CREAD | HUPCL,
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.c_cc = INIT_C_CC,
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.c_ispeed = 38400,
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.c_ospeed = 38400
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};
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/**
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* vcc_table_add() - Add VCC port to the VCC table
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* @port: pointer to the VCC port
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*
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* Return: index of the port in the VCC table on success,
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* -1 on failure
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*/
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static int vcc_table_add(struct vcc_port *port)
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{
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unsigned long flags;
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int i;
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spin_lock_irqsave(&vcc_table_lock, flags);
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for (i = VCC_MINOR_START; i < VCC_MAX_PORTS; i++) {
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if (!vcc_table[i]) {
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vcc_table[i] = port;
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break;
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}
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}
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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if (i < VCC_MAX_PORTS)
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return i;
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else
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return -1;
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}
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/**
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* vcc_table_remove() - Removes a VCC port from the VCC table
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* @index: Index into the VCC table
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*/
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static void vcc_table_remove(unsigned long index)
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{
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unsigned long flags;
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if (WARN_ON(index >= VCC_MAX_PORTS))
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return;
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spin_lock_irqsave(&vcc_table_lock, flags);
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vcc_table[index] = NULL;
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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}
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/**
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* vcc_get() - Gets a reference to VCC port
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* @index: Index into the VCC table
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* @excl: Indicates if an exclusive access is requested
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*
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* Return: reference to the VCC port, if found
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* NULL, if port not found
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*/
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static struct vcc_port *vcc_get(unsigned long index, bool excl)
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{
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struct vcc_port *port;
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unsigned long flags;
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try_again:
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spin_lock_irqsave(&vcc_table_lock, flags);
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port = vcc_table[index];
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if (!port) {
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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return NULL;
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}
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if (!excl) {
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if (port->excl_locked) {
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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udelay(VCC_REF_DELAY);
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goto try_again;
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}
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port->refcnt++;
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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return port;
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}
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if (port->refcnt) {
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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/* Threads wanting exclusive access will wait half the time,
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* probably giving them higher priority in the case of
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* multiple waiters.
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*/
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udelay(VCC_REF_DELAY/2);
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goto try_again;
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}
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port->refcnt++;
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port->excl_locked = true;
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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return port;
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}
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/**
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* vcc_put() - Returns a reference to VCC port
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* @port: pointer to VCC port
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* @excl: Indicates if the returned reference is an exclusive reference
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*
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* Note: It's the caller's responsibility to ensure the correct value
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* for the excl flag
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*/
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static void vcc_put(struct vcc_port *port, bool excl)
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{
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unsigned long flags;
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if (!port)
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return;
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spin_lock_irqsave(&vcc_table_lock, flags);
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/* check if caller attempted to put with the wrong flags */
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if (WARN_ON((excl && !port->excl_locked) ||
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(!excl && port->excl_locked)))
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goto done;
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port->refcnt--;
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if (excl)
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port->excl_locked = false;
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done:
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spin_unlock_irqrestore(&vcc_table_lock, flags);
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}
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/**
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* vcc_get_ne() - Get a non-exclusive reference to VCC port
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* @index: Index into the VCC table
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*
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* Gets a non-exclusive reference to VCC port, if it's not removed
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*
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* Return: pointer to the VCC port, if found
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* NULL, if port not found
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*/
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static struct vcc_port *vcc_get_ne(unsigned long index)
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{
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struct vcc_port *port;
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port = vcc_get(index, false);
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if (port && port->removed) {
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vcc_put(port, false);
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return NULL;
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}
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return port;
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}
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static void vcc_kick_rx(struct vcc_port *port)
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{
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struct vio_driver_state *vio = &port->vio;
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assert_spin_locked(&port->lock);
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if (!timer_pending(&port->rx_timer) && !port->removed) {
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disable_irq_nosync(vio->vdev->rx_irq);
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port->rx_timer.expires = (jiffies + 1);
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add_timer(&port->rx_timer);
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}
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}
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static void vcc_kick_tx(struct vcc_port *port)
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{
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assert_spin_locked(&port->lock);
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if (!timer_pending(&port->tx_timer) && !port->removed) {
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port->tx_timer.expires = (jiffies + 1);
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add_timer(&port->tx_timer);
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}
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}
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static int vcc_rx_check(struct tty_struct *tty, int size)
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{
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if (WARN_ON(!tty || !tty->port))
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return 1;
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/* tty_buffer_request_room won't sleep because it uses
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* GFP_ATOMIC flag to allocate buffer
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*/
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if (test_bit(TTY_THROTTLED, &tty->flags) ||
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(tty_buffer_request_room(tty->port, VCC_BUFF_LEN) < VCC_BUFF_LEN))
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return 0;
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return 1;
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}
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static int vcc_rx(struct tty_struct *tty, char *buf, int size)
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{
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int len = 0;
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if (WARN_ON(!tty || !tty->port))
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return len;
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len = tty_insert_flip_string(tty->port, buf, size);
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if (len)
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tty_flip_buffer_push(tty->port);
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return len;
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}
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static int vcc_ldc_read(struct vcc_port *port)
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{
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struct vio_driver_state *vio = &port->vio;
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struct tty_struct *tty;
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struct vio_vcc pkt;
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int rv = 0;
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tty = port->tty;
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if (!tty) {
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rv = ldc_rx_reset(vio->lp);
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vccdbg("VCC: reset rx q: rv=%d\n", rv);
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goto done;
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}
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/* Read as long as LDC has incoming data. */
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while (1) {
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if (!vcc_rx_check(tty, VIO_VCC_MTU_SIZE)) {
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vcc_kick_rx(port);
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break;
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}
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vccdbgl(vio->lp);
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rv = ldc_read(vio->lp, &pkt, sizeof(pkt));
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if (rv <= 0)
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break;
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vccdbg("VCC: ldc_read()=%d\n", rv);
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vccdbg("TAG [%02x:%02x:%04x:%08x]\n",
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pkt.tag.type, pkt.tag.stype,
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pkt.tag.stype_env, pkt.tag.sid);
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if (pkt.tag.type == VIO_TYPE_DATA) {
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vccdbgp(pkt);
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/* vcc_rx_check ensures memory availability */
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vcc_rx(tty, pkt.data, pkt.tag.stype);
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} else {
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pr_err("VCC: unknown msg [%02x:%02x:%04x:%08x]\n",
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pkt.tag.type, pkt.tag.stype,
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pkt.tag.stype_env, pkt.tag.sid);
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rv = -ECONNRESET;
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break;
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}
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WARN_ON(rv != LDC_PACKET_SIZE);
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}
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done:
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return rv;
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}
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static void vcc_rx_timer(struct timer_list *t)
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{
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struct vcc_port *port = from_timer(port, t, rx_timer);
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struct vio_driver_state *vio;
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unsigned long flags;
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int rv;
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spin_lock_irqsave(&port->lock, flags);
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port->rx_timer.expires = 0;
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vio = &port->vio;
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enable_irq(vio->vdev->rx_irq);
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if (!port->tty || port->removed)
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goto done;
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rv = vcc_ldc_read(port);
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if (rv == -ECONNRESET)
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vio_conn_reset(vio);
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done:
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spin_unlock_irqrestore(&port->lock, flags);
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vcc_put(port, false);
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}
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static void vcc_tx_timer(struct timer_list *t)
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{
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struct vcc_port *port = from_timer(port, t, tx_timer);
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struct vio_vcc *pkt;
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unsigned long flags;
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int tosend = 0;
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int rv;
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spin_lock_irqsave(&port->lock, flags);
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port->tx_timer.expires = 0;
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if (!port->tty || port->removed)
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goto done;
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tosend = min(VCC_BUFF_LEN, port->chars_in_buffer);
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if (!tosend)
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goto done;
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pkt = &port->buffer;
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pkt->tag.type = VIO_TYPE_DATA;
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pkt->tag.stype = tosend;
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vccdbgl(port->vio.lp);
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rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend));
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WARN_ON(!rv);
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if (rv < 0) {
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vccdbg("VCC: ldc_write()=%d\n", rv);
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vcc_kick_tx(port);
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} else {
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struct tty_struct *tty = port->tty;
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port->chars_in_buffer = 0;
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if (tty)
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tty_wakeup(tty);
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}
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done:
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spin_unlock_irqrestore(&port->lock, flags);
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vcc_put(port, false);
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}
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/**
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* vcc_event() - LDC event processing engine
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* @arg: VCC private data
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* @event: LDC event
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*
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* Handles LDC events for VCC
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*/
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static void vcc_event(void *arg, int event)
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{
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struct vio_driver_state *vio;
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struct vcc_port *port;
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unsigned long flags;
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int rv;
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port = arg;
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vio = &port->vio;
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spin_lock_irqsave(&port->lock, flags);
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switch (event) {
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case LDC_EVENT_RESET:
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case LDC_EVENT_UP:
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vio_link_state_change(vio, event);
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break;
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case LDC_EVENT_DATA_READY:
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rv = vcc_ldc_read(port);
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if (rv == -ECONNRESET)
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vio_conn_reset(vio);
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break;
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default:
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pr_err("VCC: unexpected LDC event(%d)\n", event);
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}
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|
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spin_unlock_irqrestore(&port->lock, flags);
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}
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|
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static struct ldc_channel_config vcc_ldc_cfg = {
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.event = vcc_event,
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.mtu = VIO_VCC_MTU_SIZE,
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.mode = LDC_MODE_RAW,
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.debug = 0,
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};
|
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|
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/* Ordered from largest major to lowest */
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static struct vio_version vcc_versions[] = {
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{ .major = 1, .minor = 0 },
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};
|
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|
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static struct tty_port_operations vcc_port_ops = { 0 };
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|
|
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static ssize_t domain_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
|
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{
|
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struct vcc_port *port;
|
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int rv;
|
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|
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port = dev_get_drvdata(dev);
|
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if (!port)
|
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return -ENODEV;
|
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|
|
rv = scnprintf(buf, PAGE_SIZE, "%s\n", port->domain);
|
|
|
|
return rv;
|
|
}
|
|
|
|
static int vcc_send_ctl(struct vcc_port *port, int ctl)
|
|
{
|
|
struct vio_vcc pkt;
|
|
int rv;
|
|
|
|
pkt.tag.type = VIO_TYPE_CTRL;
|
|
pkt.tag.sid = ctl;
|
|
pkt.tag.stype = 0;
|
|
|
|
rv = ldc_write(port->vio.lp, &pkt, sizeof(pkt.tag));
|
|
WARN_ON(!rv);
|
|
vccdbg("VCC: ldc_write(%ld)=%d\n", sizeof(pkt.tag), rv);
|
|
|
|
return rv;
|
|
}
|
|
|
|
static ssize_t break_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct vcc_port *port;
|
|
unsigned long flags;
|
|
int rv = count;
|
|
int brk;
|
|
|
|
port = dev_get_drvdata(dev);
|
|
if (!port)
|
|
return -ENODEV;
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
if (sscanf(buf, "%ud", &brk) != 1 || brk != 1)
|
|
rv = -EINVAL;
|
|
else if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0)
|
|
vcc_kick_tx(port);
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
return rv;
|
|
}
|
|
|
|
static DEVICE_ATTR_ADMIN_RO(domain);
|
|
static DEVICE_ATTR_WO(break);
|
|
|
|
static struct attribute *vcc_sysfs_entries[] = {
|
|
&dev_attr_domain.attr,
|
|
&dev_attr_break.attr,
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group vcc_attribute_group = {
|
|
.name = NULL,
|
|
.attrs = vcc_sysfs_entries,
|
|
};
|
|
|
|
/**
|
|
* vcc_probe() - Initialize VCC port
|
|
* @vdev: Pointer to VIO device of the new VCC port
|
|
* @id: VIO device ID
|
|
*
|
|
* Initializes a VCC port to receive serial console data from
|
|
* the guest domain. Sets up a TTY end point on the control
|
|
* domain. Sets up VIO/LDC link between the guest & control
|
|
* domain endpoints.
|
|
*
|
|
* Return: status of the probe
|
|
*/
|
|
static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
|
|
{
|
|
struct mdesc_handle *hp;
|
|
struct vcc_port *port;
|
|
struct device *dev;
|
|
const char *domain;
|
|
char *name;
|
|
u64 node;
|
|
int rv;
|
|
|
|
vccdbg("VCC: name=%s\n", dev_name(&vdev->dev));
|
|
|
|
if (!vcc_tty_driver) {
|
|
pr_err("VCC: TTY driver not registered\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
port = kzalloc(sizeof(struct vcc_port), GFP_KERNEL);
|
|
if (!port)
|
|
return -ENOMEM;
|
|
|
|
name = kstrdup(dev_name(&vdev->dev), GFP_KERNEL);
|
|
|
|
rv = vio_driver_init(&port->vio, vdev, VDEV_CONSOLE_CON, vcc_versions,
|
|
ARRAY_SIZE(vcc_versions), NULL, name);
|
|
if (rv)
|
|
goto free_port;
|
|
|
|
port->vio.debug = vcc_dbg_vio;
|
|
vcc_ldc_cfg.debug = vcc_dbg_ldc;
|
|
|
|
rv = vio_ldc_alloc(&port->vio, &vcc_ldc_cfg, port);
|
|
if (rv)
|
|
goto free_port;
|
|
|
|
spin_lock_init(&port->lock);
|
|
|
|
port->index = vcc_table_add(port);
|
|
if (port->index == -1) {
|
|
pr_err("VCC: no more TTY indices left for allocation\n");
|
|
rv = -ENOMEM;
|
|
goto free_ldc;
|
|
}
|
|
|
|
/* Register the device using VCC table index as TTY index */
|
|
dev = tty_register_device(vcc_tty_driver, port->index, &vdev->dev);
|
|
if (IS_ERR(dev)) {
|
|
rv = PTR_ERR(dev);
|
|
goto free_table;
|
|
}
|
|
|
|
hp = mdesc_grab();
|
|
|
|
node = vio_vdev_node(hp, vdev);
|
|
if (node == MDESC_NODE_NULL) {
|
|
rv = -ENXIO;
|
|
mdesc_release(hp);
|
|
goto unreg_tty;
|
|
}
|
|
|
|
domain = mdesc_get_property(hp, node, "vcc-domain-name", NULL);
|
|
if (!domain) {
|
|
rv = -ENXIO;
|
|
mdesc_release(hp);
|
|
goto unreg_tty;
|
|
}
|
|
port->domain = kstrdup(domain, GFP_KERNEL);
|
|
|
|
mdesc_release(hp);
|
|
|
|
rv = sysfs_create_group(&vdev->dev.kobj, &vcc_attribute_group);
|
|
if (rv)
|
|
goto free_domain;
|
|
|
|
timer_setup(&port->rx_timer, vcc_rx_timer, 0);
|
|
timer_setup(&port->tx_timer, vcc_tx_timer, 0);
|
|
|
|
dev_set_drvdata(&vdev->dev, port);
|
|
|
|
/* It's possible to receive IRQs in the middle of vio_port_up. Disable
|
|
* IRQs until the port is up.
|
|
*/
|
|
disable_irq_nosync(vdev->rx_irq);
|
|
vio_port_up(&port->vio);
|
|
enable_irq(vdev->rx_irq);
|
|
|
|
return 0;
|
|
|
|
free_domain:
|
|
kfree(port->domain);
|
|
unreg_tty:
|
|
tty_unregister_device(vcc_tty_driver, port->index);
|
|
free_table:
|
|
vcc_table_remove(port->index);
|
|
free_ldc:
|
|
vio_ldc_free(&port->vio);
|
|
free_port:
|
|
kfree(name);
|
|
kfree(port);
|
|
|
|
return rv;
|
|
}
|
|
|
|
/**
|
|
* vcc_remove() - Terminate a VCC port
|
|
* @vdev: Pointer to VIO device of the VCC port
|
|
*
|
|
* Terminates a VCC port. Sets up the teardown of TTY and
|
|
* VIO/LDC link between guest and primary domains.
|
|
*
|
|
* Return: status of removal
|
|
*/
|
|
static void vcc_remove(struct vio_dev *vdev)
|
|
{
|
|
struct vcc_port *port = dev_get_drvdata(&vdev->dev);
|
|
|
|
del_timer_sync(&port->rx_timer);
|
|
del_timer_sync(&port->tx_timer);
|
|
|
|
/* If there's a process with the device open, do a synchronous
|
|
* hangup of the TTY. This *may* cause the process to call close
|
|
* asynchronously, but it's not guaranteed.
|
|
*/
|
|
if (port->tty)
|
|
tty_vhangup(port->tty);
|
|
|
|
/* Get exclusive reference to VCC, ensures that there are no other
|
|
* clients to this port. This cannot fail.
|
|
*/
|
|
vcc_get(port->index, true);
|
|
|
|
tty_unregister_device(vcc_tty_driver, port->index);
|
|
|
|
del_timer_sync(&port->vio.timer);
|
|
vio_ldc_free(&port->vio);
|
|
sysfs_remove_group(&vdev->dev.kobj, &vcc_attribute_group);
|
|
dev_set_drvdata(&vdev->dev, NULL);
|
|
if (port->tty) {
|
|
port->removed = true;
|
|
vcc_put(port, true);
|
|
} else {
|
|
vcc_table_remove(port->index);
|
|
|
|
kfree(port->vio.name);
|
|
kfree(port->domain);
|
|
kfree(port);
|
|
}
|
|
}
|
|
|
|
static const struct vio_device_id vcc_match[] = {
|
|
{
|
|
.type = "vcc-port",
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(vio, vcc_match);
|
|
|
|
static struct vio_driver vcc_driver = {
|
|
.id_table = vcc_match,
|
|
.probe = vcc_probe,
|
|
.remove = vcc_remove,
|
|
.name = "vcc",
|
|
};
|
|
|
|
static int vcc_open(struct tty_struct *tty, struct file *vcc_file)
|
|
{
|
|
struct vcc_port *port;
|
|
|
|
if (tty->count > 1)
|
|
return -EBUSY;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: open: Failed to find VCC port\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (unlikely(!port->vio.lp)) {
|
|
pr_err("VCC: open: LDC channel not configured\n");
|
|
vcc_put(port, false);
|
|
return -EPIPE;
|
|
}
|
|
vccdbgl(port->vio.lp);
|
|
|
|
vcc_put(port, false);
|
|
|
|
if (unlikely(!tty->port)) {
|
|
pr_err("VCC: open: TTY port not found\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
if (unlikely(!tty->port->ops)) {
|
|
pr_err("VCC: open: TTY ops not defined\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
return tty_port_open(tty->port, tty, vcc_file);
|
|
}
|
|
|
|
static void vcc_close(struct tty_struct *tty, struct file *vcc_file)
|
|
{
|
|
if (unlikely(tty->count > 1))
|
|
return;
|
|
|
|
if (unlikely(!tty->port)) {
|
|
pr_err("VCC: close: TTY port not found\n");
|
|
return;
|
|
}
|
|
|
|
tty_port_close(tty->port, tty, vcc_file);
|
|
}
|
|
|
|
static void vcc_ldc_hup(struct vcc_port *port)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
if (vcc_send_ctl(port, VCC_CTL_HUP) < 0)
|
|
vcc_kick_tx(port);
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
}
|
|
|
|
static void vcc_hangup(struct tty_struct *tty)
|
|
{
|
|
struct vcc_port *port;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: hangup: Failed to find VCC port\n");
|
|
return;
|
|
}
|
|
|
|
if (unlikely(!tty->port)) {
|
|
pr_err("VCC: hangup: TTY port not found\n");
|
|
vcc_put(port, false);
|
|
return;
|
|
}
|
|
|
|
vcc_ldc_hup(port);
|
|
|
|
vcc_put(port, false);
|
|
|
|
tty_port_hangup(tty->port);
|
|
}
|
|
|
|
static int vcc_write(struct tty_struct *tty, const unsigned char *buf,
|
|
int count)
|
|
{
|
|
struct vcc_port *port;
|
|
struct vio_vcc *pkt;
|
|
unsigned long flags;
|
|
int total_sent = 0;
|
|
int tosend = 0;
|
|
int rv = -EINVAL;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: write: Failed to find VCC port");
|
|
return -ENODEV;
|
|
}
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
pkt = &port->buffer;
|
|
pkt->tag.type = VIO_TYPE_DATA;
|
|
|
|
while (count > 0) {
|
|
/* Minimum of data to write and space available */
|
|
tosend = min(count, (VCC_BUFF_LEN - port->chars_in_buffer));
|
|
|
|
if (!tosend)
|
|
break;
|
|
|
|
memcpy(&pkt->data[port->chars_in_buffer], &buf[total_sent],
|
|
tosend);
|
|
port->chars_in_buffer += tosend;
|
|
pkt->tag.stype = tosend;
|
|
|
|
vccdbg("TAG [%02x:%02x:%04x:%08x]\n", pkt->tag.type,
|
|
pkt->tag.stype, pkt->tag.stype_env, pkt->tag.sid);
|
|
vccdbg("DATA [%s]\n", pkt->data);
|
|
vccdbgl(port->vio.lp);
|
|
|
|
/* Since we know we have enough room in VCC buffer for tosend
|
|
* we record that it was sent regardless of whether the
|
|
* hypervisor actually took it because we have it buffered.
|
|
*/
|
|
rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend));
|
|
vccdbg("VCC: write: ldc_write(%d)=%d\n",
|
|
(VIO_TAG_SIZE + tosend), rv);
|
|
|
|
total_sent += tosend;
|
|
count -= tosend;
|
|
if (rv < 0) {
|
|
vcc_kick_tx(port);
|
|
break;
|
|
}
|
|
|
|
port->chars_in_buffer = 0;
|
|
}
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
vcc_put(port, false);
|
|
|
|
vccdbg("VCC: write: total=%d rv=%d", total_sent, rv);
|
|
|
|
return total_sent ? total_sent : rv;
|
|
}
|
|
|
|
static unsigned int vcc_write_room(struct tty_struct *tty)
|
|
{
|
|
struct vcc_port *port;
|
|
unsigned int num;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: write_room: Failed to find VCC port\n");
|
|
return 0;
|
|
}
|
|
|
|
num = VCC_BUFF_LEN - port->chars_in_buffer;
|
|
|
|
vcc_put(port, false);
|
|
|
|
return num;
|
|
}
|
|
|
|
static unsigned int vcc_chars_in_buffer(struct tty_struct *tty)
|
|
{
|
|
struct vcc_port *port;
|
|
unsigned int num;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: chars_in_buffer: Failed to find VCC port\n");
|
|
return 0;
|
|
}
|
|
|
|
num = port->chars_in_buffer;
|
|
|
|
vcc_put(port, false);
|
|
|
|
return num;
|
|
}
|
|
|
|
static int vcc_break_ctl(struct tty_struct *tty, int state)
|
|
{
|
|
struct vcc_port *port;
|
|
unsigned long flags;
|
|
|
|
port = vcc_get_ne(tty->index);
|
|
if (unlikely(!port)) {
|
|
pr_err("VCC: break_ctl: Failed to find VCC port\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Turn off break */
|
|
if (state == 0) {
|
|
vcc_put(port, false);
|
|
return 0;
|
|
}
|
|
|
|
spin_lock_irqsave(&port->lock, flags);
|
|
|
|
if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0)
|
|
vcc_kick_tx(port);
|
|
|
|
spin_unlock_irqrestore(&port->lock, flags);
|
|
|
|
vcc_put(port, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int vcc_install(struct tty_driver *driver, struct tty_struct *tty)
|
|
{
|
|
struct vcc_port *port_vcc;
|
|
struct tty_port *port_tty;
|
|
int ret;
|
|
|
|
if (tty->index >= VCC_MAX_PORTS)
|
|
return -EINVAL;
|
|
|
|
ret = tty_standard_install(driver, tty);
|
|
if (ret)
|
|
return ret;
|
|
|
|
port_tty = kzalloc(sizeof(struct tty_port), GFP_KERNEL);
|
|
if (!port_tty)
|
|
return -ENOMEM;
|
|
|
|
port_vcc = vcc_get(tty->index, true);
|
|
if (!port_vcc) {
|
|
pr_err("VCC: install: Failed to find VCC port\n");
|
|
tty->port = NULL;
|
|
kfree(port_tty);
|
|
return -ENODEV;
|
|
}
|
|
|
|
tty_port_init(port_tty);
|
|
port_tty->ops = &vcc_port_ops;
|
|
tty->port = port_tty;
|
|
|
|
port_vcc->tty = tty;
|
|
|
|
vcc_put(port_vcc, true);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void vcc_cleanup(struct tty_struct *tty)
|
|
{
|
|
struct vcc_port *port;
|
|
|
|
port = vcc_get(tty->index, true);
|
|
if (port) {
|
|
port->tty = NULL;
|
|
|
|
if (port->removed) {
|
|
vcc_table_remove(tty->index);
|
|
kfree(port->vio.name);
|
|
kfree(port->domain);
|
|
kfree(port);
|
|
} else {
|
|
vcc_put(port, true);
|
|
}
|
|
}
|
|
|
|
tty_port_destroy(tty->port);
|
|
kfree(tty->port);
|
|
tty->port = NULL;
|
|
}
|
|
|
|
static const struct tty_operations vcc_ops = {
|
|
.open = vcc_open,
|
|
.close = vcc_close,
|
|
.hangup = vcc_hangup,
|
|
.write = vcc_write,
|
|
.write_room = vcc_write_room,
|
|
.chars_in_buffer = vcc_chars_in_buffer,
|
|
.break_ctl = vcc_break_ctl,
|
|
.install = vcc_install,
|
|
.cleanup = vcc_cleanup,
|
|
};
|
|
|
|
#define VCC_TTY_FLAGS (TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_REAL_RAW)
|
|
|
|
static int vcc_tty_init(void)
|
|
{
|
|
int rv;
|
|
|
|
vcc_tty_driver = tty_alloc_driver(VCC_MAX_PORTS, VCC_TTY_FLAGS);
|
|
if (IS_ERR(vcc_tty_driver)) {
|
|
pr_err("VCC: TTY driver alloc failed\n");
|
|
return PTR_ERR(vcc_tty_driver);
|
|
}
|
|
|
|
vcc_tty_driver->driver_name = "vcc";
|
|
vcc_tty_driver->name = "vcc";
|
|
|
|
vcc_tty_driver->minor_start = VCC_MINOR_START;
|
|
vcc_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
|
|
vcc_tty_driver->init_termios = vcc_tty_termios;
|
|
|
|
tty_set_operations(vcc_tty_driver, &vcc_ops);
|
|
|
|
rv = tty_register_driver(vcc_tty_driver);
|
|
if (rv) {
|
|
pr_err("VCC: TTY driver registration failed\n");
|
|
tty_driver_kref_put(vcc_tty_driver);
|
|
vcc_tty_driver = NULL;
|
|
return rv;
|
|
}
|
|
|
|
vccdbg("VCC: TTY driver registered\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void vcc_tty_exit(void)
|
|
{
|
|
tty_unregister_driver(vcc_tty_driver);
|
|
tty_driver_kref_put(vcc_tty_driver);
|
|
vccdbg("VCC: TTY driver unregistered\n");
|
|
|
|
vcc_tty_driver = NULL;
|
|
}
|
|
|
|
static int __init vcc_init(void)
|
|
{
|
|
int rv;
|
|
|
|
rv = vcc_tty_init();
|
|
if (rv) {
|
|
pr_err("VCC: TTY init failed\n");
|
|
return rv;
|
|
}
|
|
|
|
rv = vio_register_driver(&vcc_driver);
|
|
if (rv) {
|
|
pr_err("VCC: VIO driver registration failed\n");
|
|
vcc_tty_exit();
|
|
} else {
|
|
vccdbg("VCC: VIO driver registered successfully\n");
|
|
}
|
|
|
|
return rv;
|
|
}
|
|
|
|
static void __exit vcc_exit(void)
|
|
{
|
|
vio_unregister_driver(&vcc_driver);
|
|
vccdbg("VCC: VIO driver unregistered\n");
|
|
vcc_tty_exit();
|
|
vccdbg("VCC: TTY driver unregistered\n");
|
|
}
|
|
|
|
module_init(vcc_init);
|
|
module_exit(vcc_exit);
|