linux/drivers/pcmcia/db1xxx_ss.c
Gustavo A. R. Silva 5f163f331b pcmcia: db1xxx_ss: Mark expected switch fall-throughs
Mark switch cases where we are expecting to fall through.

This patch fixes the following warnings (Building: db1xxx_defconfig mips):

drivers/pcmcia/db1xxx_ss.c:257:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/pcmcia/db1xxx_ss.c:269:3: warning: this statement may fall through [-Wimplicit-fallthrough=]

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2019-08-09 19:53:04 -05:00

604 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* PCMCIA socket code for the Alchemy Db1xxx/Pb1xxx boards.
*
* Copyright (c) 2009 Manuel Lauss <manuel.lauss@gmail.com>
*
*/
/* This is a fairly generic PCMCIA socket driver suitable for the
* following Alchemy Development boards:
* Db1000, Db/Pb1500, Db/Pb1100, Db/Pb1550, Db/Pb1200, Db1300
*
* The Db1000 is used as a reference: Per-socket card-, carddetect- and
* statuschange IRQs connected to SoC GPIOs, control and status register
* bits arranged in per-socket groups in an external PLD. All boards
* listed here use this layout, including bit positions and meanings.
* Of course there are exceptions in later boards:
*
* - Pb1100/Pb1500: single socket only; voltage key bits VS are
* at STATUS[5:4] (instead of STATUS[1:0]).
* - Au1200-based: additional card-eject irqs, irqs not gpios!
* - Db1300: Db1200-like, no pwr ctrl, single socket (#1).
*/
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/pm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/resource.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <pcmcia/ss.h>
#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-db1x00/bcsr.h>
#define MEM_MAP_SIZE 0x400000
#define IO_MAP_SIZE 0x1000
struct db1x_pcmcia_sock {
struct pcmcia_socket socket;
int nr; /* socket number */
void *virt_io;
phys_addr_t phys_io;
phys_addr_t phys_attr;
phys_addr_t phys_mem;
/* previous flags for set_socket() */
unsigned int old_flags;
/* interrupt sources: linux irq numbers! */
int insert_irq; /* default carddetect irq */
int stschg_irq; /* card-status-change irq */
int card_irq; /* card irq */
int eject_irq; /* db1200/pb1200 have these */
int insert_gpio; /* db1000 carddetect gpio */
#define BOARD_TYPE_DEFAULT 0 /* most boards */
#define BOARD_TYPE_DB1200 1 /* IRQs aren't gpios */
#define BOARD_TYPE_PB1100 2 /* VS bits slightly different */
#define BOARD_TYPE_DB1300 3 /* no power control */
int board_type;
};
#define to_db1x_socket(x) container_of(x, struct db1x_pcmcia_sock, socket)
static int db1300_card_inserted(struct db1x_pcmcia_sock *sock)
{
return bcsr_read(BCSR_SIGSTAT) & (1 << 8);
}
/* DB/PB1200: check CPLD SIGSTATUS register bit 10/12 */
static int db1200_card_inserted(struct db1x_pcmcia_sock *sock)
{
unsigned short sigstat;
sigstat = bcsr_read(BCSR_SIGSTAT);
return sigstat & 1 << (8 + 2 * sock->nr);
}
/* carddetect gpio: low-active */
static int db1000_card_inserted(struct db1x_pcmcia_sock *sock)
{
return !gpio_get_value(sock->insert_gpio);
}
static int db1x_card_inserted(struct db1x_pcmcia_sock *sock)
{
switch (sock->board_type) {
case BOARD_TYPE_DB1200:
return db1200_card_inserted(sock);
case BOARD_TYPE_DB1300:
return db1300_card_inserted(sock);
default:
return db1000_card_inserted(sock);
}
}
/* STSCHG tends to bounce heavily when cards are inserted/ejected.
* To avoid this, the interrupt is normally disabled and only enabled
* after reset to a card has been de-asserted.
*/
static inline void set_stschg(struct db1x_pcmcia_sock *sock, int en)
{
if (sock->stschg_irq != -1) {
if (en)
enable_irq(sock->stschg_irq);
else
disable_irq(sock->stschg_irq);
}
}
static irqreturn_t db1000_pcmcia_cdirq(int irq, void *data)
{
struct db1x_pcmcia_sock *sock = data;
pcmcia_parse_events(&sock->socket, SS_DETECT);
return IRQ_HANDLED;
}
static irqreturn_t db1000_pcmcia_stschgirq(int irq, void *data)
{
struct db1x_pcmcia_sock *sock = data;
pcmcia_parse_events(&sock->socket, SS_STSCHG);
return IRQ_HANDLED;
}
/* Db/Pb1200 have separate per-socket insertion and ejection
* interrupts which stay asserted as long as the card is
* inserted/missing. The one which caused us to be called
* needs to be disabled and the other one enabled.
*/
static irqreturn_t db1200_pcmcia_cdirq(int irq, void *data)
{
disable_irq_nosync(irq);
return IRQ_WAKE_THREAD;
}
static irqreturn_t db1200_pcmcia_cdirq_fn(int irq, void *data)
{
struct db1x_pcmcia_sock *sock = data;
/* Wait a bit for the signals to stop bouncing. */
msleep(100);
if (irq == sock->insert_irq)
enable_irq(sock->eject_irq);
else
enable_irq(sock->insert_irq);
pcmcia_parse_events(&sock->socket, SS_DETECT);
return IRQ_HANDLED;
}
static int db1x_pcmcia_setup_irqs(struct db1x_pcmcia_sock *sock)
{
int ret;
if (sock->stschg_irq != -1) {
ret = request_irq(sock->stschg_irq, db1000_pcmcia_stschgirq,
0, "pcmcia_stschg", sock);
if (ret)
return ret;
}
/* Db/Pb1200 have separate per-socket insertion and ejection
* interrupts, which should show edge behaviour but don't.
* So interrupts are disabled until both insertion and
* ejection handler have been registered and the currently
* active one disabled.
*/
if ((sock->board_type == BOARD_TYPE_DB1200) ||
(sock->board_type == BOARD_TYPE_DB1300)) {
ret = request_threaded_irq(sock->insert_irq, db1200_pcmcia_cdirq,
db1200_pcmcia_cdirq_fn, 0, "pcmcia_insert", sock);
if (ret)
goto out1;
ret = request_threaded_irq(sock->eject_irq, db1200_pcmcia_cdirq,
db1200_pcmcia_cdirq_fn, 0, "pcmcia_eject", sock);
if (ret) {
free_irq(sock->insert_irq, sock);
goto out1;
}
/* enable the currently silent one */
if (db1x_card_inserted(sock))
enable_irq(sock->eject_irq);
else
enable_irq(sock->insert_irq);
} else {
/* all other (older) Db1x00 boards use a GPIO to show
* card detection status: use both-edge triggers.
*/
irq_set_irq_type(sock->insert_irq, IRQ_TYPE_EDGE_BOTH);
ret = request_irq(sock->insert_irq, db1000_pcmcia_cdirq,
0, "pcmcia_carddetect", sock);
if (ret)
goto out1;
}
return 0; /* all done */
out1:
if (sock->stschg_irq != -1)
free_irq(sock->stschg_irq, sock);
return ret;
}
static void db1x_pcmcia_free_irqs(struct db1x_pcmcia_sock *sock)
{
if (sock->stschg_irq != -1)
free_irq(sock->stschg_irq, sock);
free_irq(sock->insert_irq, sock);
if (sock->eject_irq != -1)
free_irq(sock->eject_irq, sock);
}
/*
* configure a PCMCIA socket on the Db1x00 series of boards (and
* compatibles).
*
* 2 external registers are involved:
* pcmcia_status (offset 0x04): bits [0:1/2:3]: read card voltage id
* pcmcia_control(offset 0x10):
* bits[0:1] set vcc for card
* bits[2:3] set vpp for card
* bit 4: enable data buffers
* bit 7: reset# for card
* add 8 for second socket.
*/
static int db1x_pcmcia_configure(struct pcmcia_socket *skt,
struct socket_state_t *state)
{
struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
unsigned short cr_clr, cr_set;
unsigned int changed;
int v, p, ret;
/* card voltage setup */
cr_clr = (0xf << (sock->nr * 8)); /* clear voltage settings */
cr_set = 0;
v = p = ret = 0;
switch (state->Vcc) {
case 50:
++v;
/* fall through */
case 33:
++v;
/* fall through */
case 0:
break;
default:
printk(KERN_INFO "pcmcia%d unsupported Vcc %d\n",
sock->nr, state->Vcc);
}
switch (state->Vpp) {
case 12:
++p;
/* fall through */
case 33:
case 50:
++p;
/* fall through */
case 0:
break;
default:
printk(KERN_INFO "pcmcia%d unsupported Vpp %d\n",
sock->nr, state->Vpp);
}
/* sanity check: Vpp must be 0, 12, or Vcc */
if (((state->Vcc == 33) && (state->Vpp == 50)) ||
((state->Vcc == 50) && (state->Vpp == 33))) {
printk(KERN_INFO "pcmcia%d bad Vcc/Vpp combo (%d %d)\n",
sock->nr, state->Vcc, state->Vpp);
v = p = 0;
ret = -EINVAL;
}
/* create new voltage code */
if (sock->board_type != BOARD_TYPE_DB1300)
cr_set |= ((v << 2) | p) << (sock->nr * 8);
changed = state->flags ^ sock->old_flags;
if (changed & SS_RESET) {
if (state->flags & SS_RESET) {
set_stschg(sock, 0);
/* assert reset, disable io buffers */
cr_clr |= (1 << (7 + (sock->nr * 8)));
cr_clr |= (1 << (4 + (sock->nr * 8)));
} else {
/* de-assert reset, enable io buffers */
cr_set |= 1 << (7 + (sock->nr * 8));
cr_set |= 1 << (4 + (sock->nr * 8));
}
}
/* update PCMCIA configuration */
bcsr_mod(BCSR_PCMCIA, cr_clr, cr_set);
sock->old_flags = state->flags;
/* reset was taken away: give card time to initialize properly */
if ((changed & SS_RESET) && !(state->flags & SS_RESET)) {
msleep(500);
set_stschg(sock, 1);
}
return ret;
}
/* VCC bits at [3:2]/[11:10] */
#define GET_VCC(cr, socknr) \
((((cr) >> 2) >> ((socknr) * 8)) & 3)
/* VS bits at [0:1]/[3:2] */
#define GET_VS(sr, socknr) \
(((sr) >> (2 * (socknr))) & 3)
/* reset bits at [7]/[15] */
#define GET_RESET(cr, socknr) \
((cr) & (1 << (7 + (8 * (socknr)))))
static int db1x_pcmcia_get_status(struct pcmcia_socket *skt,
unsigned int *value)
{
struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
unsigned short cr, sr;
unsigned int status;
status = db1x_card_inserted(sock) ? SS_DETECT : 0;
cr = bcsr_read(BCSR_PCMCIA);
sr = bcsr_read(BCSR_STATUS);
/* PB1100/PB1500: voltage key bits are at [5:4] */
if (sock->board_type == BOARD_TYPE_PB1100)
sr >>= 4;
/* determine card type */
switch (GET_VS(sr, sock->nr)) {
case 0:
case 2:
status |= SS_3VCARD; /* 3V card */
case 3:
break; /* 5V card: set nothing */
default:
status |= SS_XVCARD; /* treated as unsupported in core */
}
/* if Vcc is not zero, we have applied power to a card */
status |= GET_VCC(cr, sock->nr) ? SS_POWERON : 0;
/* DB1300: power always on, but don't tell when no card present */
if ((sock->board_type == BOARD_TYPE_DB1300) && (status & SS_DETECT))
status = SS_POWERON | SS_3VCARD | SS_DETECT;
/* reset de-asserted? then we're ready */
status |= (GET_RESET(cr, sock->nr)) ? SS_READY : SS_RESET;
*value = status;
return 0;
}
static int db1x_pcmcia_sock_init(struct pcmcia_socket *skt)
{
return 0;
}
static int db1x_pcmcia_sock_suspend(struct pcmcia_socket *skt)
{
return 0;
}
static int au1x00_pcmcia_set_io_map(struct pcmcia_socket *skt,
struct pccard_io_map *map)
{
struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
map->start = (u32)sock->virt_io;
map->stop = map->start + IO_MAP_SIZE;
return 0;
}
static int au1x00_pcmcia_set_mem_map(struct pcmcia_socket *skt,
struct pccard_mem_map *map)
{
struct db1x_pcmcia_sock *sock = to_db1x_socket(skt);
if (map->flags & MAP_ATTRIB)
map->static_start = sock->phys_attr + map->card_start;
else
map->static_start = sock->phys_mem + map->card_start;
return 0;
}
static struct pccard_operations db1x_pcmcia_operations = {
.init = db1x_pcmcia_sock_init,
.suspend = db1x_pcmcia_sock_suspend,
.get_status = db1x_pcmcia_get_status,
.set_socket = db1x_pcmcia_configure,
.set_io_map = au1x00_pcmcia_set_io_map,
.set_mem_map = au1x00_pcmcia_set_mem_map,
};
static int db1x_pcmcia_socket_probe(struct platform_device *pdev)
{
struct db1x_pcmcia_sock *sock;
struct resource *r;
int ret, bid;
sock = kzalloc(sizeof(struct db1x_pcmcia_sock), GFP_KERNEL);
if (!sock)
return -ENOMEM;
sock->nr = pdev->id;
bid = BCSR_WHOAMI_BOARD(bcsr_read(BCSR_WHOAMI));
switch (bid) {
case BCSR_WHOAMI_PB1500:
case BCSR_WHOAMI_PB1500R2:
case BCSR_WHOAMI_PB1100:
sock->board_type = BOARD_TYPE_PB1100;
break;
case BCSR_WHOAMI_DB1000 ... BCSR_WHOAMI_PB1550_SDR:
sock->board_type = BOARD_TYPE_DEFAULT;
break;
case BCSR_WHOAMI_PB1200 ... BCSR_WHOAMI_DB1200:
sock->board_type = BOARD_TYPE_DB1200;
break;
case BCSR_WHOAMI_DB1300:
sock->board_type = BOARD_TYPE_DB1300;
break;
default:
printk(KERN_INFO "db1xxx-ss: unknown board %d!\n", bid);
ret = -ENODEV;
goto out0;
};
/*
* gather resources necessary and optional nice-to-haves to
* operate a socket:
* This includes IRQs for Carddetection/ejection, the card
* itself and optional status change detection.
* Also, the memory areas covered by a socket. For these
* we require the real 36bit addresses (see the au1000.h
* header for more information).
*/
/* card: irq assigned to the card itself. */
r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "card");
sock->card_irq = r ? r->start : 0;
/* insert: irq which triggers on card insertion/ejection
* BIG FAT NOTE: on DB1000/1100/1500/1550 we pass a GPIO here!
*/
r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "insert");
sock->insert_irq = r ? r->start : -1;
if (sock->board_type == BOARD_TYPE_DEFAULT) {
sock->insert_gpio = r ? r->start : -1;
sock->insert_irq = r ? gpio_to_irq(r->start) : -1;
}
/* stschg: irq which trigger on card status change (optional) */
r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "stschg");
sock->stschg_irq = r ? r->start : -1;
/* eject: irq which triggers on ejection (DB1200/PB1200 only) */
r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "eject");
sock->eject_irq = r ? r->start : -1;
ret = -ENODEV;
/* 36bit PCMCIA Attribute area address */
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-attr");
if (!r) {
printk(KERN_ERR "pcmcia%d has no 'pseudo-attr' resource!\n",
sock->nr);
goto out0;
}
sock->phys_attr = r->start;
/* 36bit PCMCIA Memory area address */
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-mem");
if (!r) {
printk(KERN_ERR "pcmcia%d has no 'pseudo-mem' resource!\n",
sock->nr);
goto out0;
}
sock->phys_mem = r->start;
/* 36bit PCMCIA IO area address */
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcmcia-io");
if (!r) {
printk(KERN_ERR "pcmcia%d has no 'pseudo-io' resource!\n",
sock->nr);
goto out0;
}
sock->phys_io = r->start;
/*
* PCMCIA client drivers use the inb/outb macros to access
* the IO registers. Since mips_io_port_base is added
* to the access address of the mips implementation of
* inb/outb, we need to subtract it here because we want
* to access the I/O or MEM address directly, without
* going through this "mips_io_port_base" mechanism.
*/
sock->virt_io = (void *)(ioremap(sock->phys_io, IO_MAP_SIZE) -
mips_io_port_base);
if (!sock->virt_io) {
printk(KERN_ERR "pcmcia%d: cannot remap IO area\n",
sock->nr);
ret = -ENOMEM;
goto out0;
}
sock->socket.ops = &db1x_pcmcia_operations;
sock->socket.owner = THIS_MODULE;
sock->socket.pci_irq = sock->card_irq;
sock->socket.features = SS_CAP_STATIC_MAP | SS_CAP_PCCARD;
sock->socket.map_size = MEM_MAP_SIZE;
sock->socket.io_offset = (unsigned long)sock->virt_io;
sock->socket.dev.parent = &pdev->dev;
sock->socket.resource_ops = &pccard_static_ops;
platform_set_drvdata(pdev, sock);
ret = db1x_pcmcia_setup_irqs(sock);
if (ret) {
printk(KERN_ERR "pcmcia%d cannot setup interrupts\n",
sock->nr);
goto out1;
}
set_stschg(sock, 0);
ret = pcmcia_register_socket(&sock->socket);
if (ret) {
printk(KERN_ERR "pcmcia%d failed to register\n", sock->nr);
goto out2;
}
printk(KERN_INFO "Alchemy Db/Pb1xxx pcmcia%d @ io/attr/mem %09llx"
"(%p) %09llx %09llx card/insert/stschg/eject irqs @ %d "
"%d %d %d\n", sock->nr, sock->phys_io, sock->virt_io,
sock->phys_attr, sock->phys_mem, sock->card_irq,
sock->insert_irq, sock->stschg_irq, sock->eject_irq);
return 0;
out2:
db1x_pcmcia_free_irqs(sock);
out1:
iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
out0:
kfree(sock);
return ret;
}
static int db1x_pcmcia_socket_remove(struct platform_device *pdev)
{
struct db1x_pcmcia_sock *sock = platform_get_drvdata(pdev);
db1x_pcmcia_free_irqs(sock);
pcmcia_unregister_socket(&sock->socket);
iounmap((void *)(sock->virt_io + (u32)mips_io_port_base));
kfree(sock);
return 0;
}
static struct platform_driver db1x_pcmcia_socket_driver = {
.driver = {
.name = "db1xxx_pcmcia",
},
.probe = db1x_pcmcia_socket_probe,
.remove = db1x_pcmcia_socket_remove,
};
module_platform_driver(db1x_pcmcia_socket_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PCMCIA Socket Services for Alchemy Db/Pb1x00 boards");
MODULE_AUTHOR("Manuel Lauss");