Commit Graph

32 Commits

Author SHA1 Message Date
Qipan Li
07d410e064 serial: sirf: fix spinlock deadlock issue
commit fb78b81142 provide a workaround for
kernel panic, but bring potential deadlock risk. that is in
sirfsoc_rx_tmo_process_tl while enter into sirfsoc_uart_pio_rx_chars
cpu hold uart_port->lock, if uart interrupt comes cpu enter into
sirfsoc_uart_isr and deadlock occurs in getting uart_port->lock.

the patch replace spin_lock version to spin_lock_irq* version to avoid
spinlock dead lock issue. let function tty_flip_buffer_push in tasklet
outof spin_lock_irq* protect area to avoid add the pair of spin_lock and
spin_unlock for tty_flip_buffer_push.
BTW drop self defined unused spinlock protect of tx_lock/rx_lock.

56274.220464] BUG: spinlock lockup suspected on CPU#0, swapper/0/0
[56274.223648]  lock: 0xc05d9db0, .magic: dead4ead, .owner: swapper/0/0,
	.owner_cpu: 0
	[56274.231278] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G
	O 3.10.35 #1
	[56274.238241] [<c0015530>] (unwind_backtrace+0x0/0xf4) from
	[<c00120d8>] (show_stack+0x10/0x14)
	[56274.246742] [<c00120d8>] (show_stack+0x10/0x14) from
	[<c01b11b0>] (do_raw_spin_lock+0x110/0x184)
	[56274.255501] [<c01b11b0>] (do_raw_spin_lock+0x110/0x184) from
	[<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c)
	[56274.264874] [<c02124c8>] (sirfsoc_uart_isr+0x20/0x42c) from
	[<c0075790>] (handle_irq_event_percpu+0x54/0x17c)
	[56274.274758] [<c0075790>] (handle_irq_event_percpu+0x54/0x17c)
	from [<c00758f4>] (handle_irq_event+0x3c/0x5c)
	[56274.284561] [<c00758f4>] (handle_irq_event+0x3c/0x5c) from
	[<c0077fa0>] (handle_level_irq+0x98/0xfc)
	[56274.293670] [<c0077fa0>] (handle_level_irq+0x98/0xfc) from
	[<c0074f44>] (generic_handle_irq+0x2c/0x3c)
	[56274.302952] [<c0074f44>] (generic_handle_irq+0x2c/0x3c) from
	[<c000ef80>] (handle_IRQ+0x40/0x90)
	[56274.311706] [<c000ef80>] (handle_IRQ+0x40/0x90) from
	[<c000dc80>] (__irq_svc+0x40/0x70)
	[56274.319697] [<c000dc80>] (__irq_svc+0x40/0x70) from
	[<c038113c>] (_raw_spin_unlock_irqrestore+0x10/0x48)
	[56274.329158] [<c038113c>]
	(_raw_spin_unlock_irqrestore+0x10/0x48) from [<c0200034>]
	(tty_port_tty_get+0x58/0x90)
	[56274.339213] [<c0200034>] (tty_port_tty_get+0x58/0x90) from
	[<c0212008>] (sirfsoc_uart_pio_rx_chars+0x1c/0xc8)
	[56274.349097] [<c0212008>]
	(sirfsoc_uart_pio_rx_chars+0x1c/0xc8) from [<c0212ef8>]
	(sirfsoc_rx_tmo_process_tl+0xe4/0x1fc)
	[56274.359853] [<c0212ef8>]
	(sirfsoc_rx_tmo_process_tl+0xe4/0x1fc) from [<c0027c04>]
	(tasklet_action+0x84/0x114)
	[56274.369739] [<c0027c04>] (tasklet_action+0x84/0x114) from
	[<c0027db4>] (__do_softirq+0x120/0x200)
	[56274.378585] [<c0027db4>] (__do_softirq+0x120/0x200) from
	[<c0027f44>] (do_softirq+0x54/0x5c)
	[56274.386998] [<c0027f44>] (do_softirq+0x54/0x5c) from
	[<c00281ec>] (irq_exit+0x9c/0xd0)
	[56274.394899] [<c00281ec>] (irq_exit+0x9c/0xd0) from
	[<c000ef84>] (handle_IRQ+0x44/0x90)
	[56274.402790] [<c000ef84>] (handle_IRQ+0x44/0x90) from
	[<c000dc80>] (__irq_svc+0x40/0x70)
	[56274.410774] [<c000dc80>] (__irq_svc+0x40/0x70) from
	[<c0288af4>] (cpuidle_enter_state+0x50/0xe0)
	[56274.419532] [<c0288af4>] (cpuidle_enter_state+0x50/0xe0) from
	[<c0288c34>] (cpuidle_idle_call+0xb0/0x148)
	[56274.429080] [<c0288c34>] (cpuidle_idle_call+0xb0/0x148) from
	[<c000f3ac>] (arch_cpu_idle+0x8/0x38)
	[56274.438016] [<c000f3ac>] (arch_cpu_idle+0x8/0x38) from
	[<c0059344>] (cpu_startup_entry+0xfc/0x140)
	[56274.446956] [<c0059344>] (cpu_startup_entry+0xfc/0x140) from
	[<c04a3a54>] (start_kernel+0x2d8/0x2e4)

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:22:43 -07:00
Barry Song
205c384f73 serial: sirf: move to writel for TXFIFO instead of writeb
All SiRFSoC UART registers are in 32-bits. If we use writeb for
TXFIFO, actually all of 32-bits are still written, for TXTIFO,
only low 8-bits are valid, so in prima2&atlas6, this causes no
problem.
But in the new atlas7, using writeb to write UART registers will
cause an imprecise data abort as HW does check the "wrong" writeb.
So move to writel and this also makes the code consistent with
sirfsoc_uart_pio_tx_chars() in which we use writel.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 12:22:43 -07:00
Qipan Li
9be16b38cf serial: sirf: move to use generic dma dt-binding to get dma channels
instead of using sirf specific dma channel property like "sirf,uart-dma-rx-channel"
and "sirf,uart-dma-tx-channel", here we move to use generic dma dt-binding to get
the channel like:
- sirf,uart-dma-rx-channel = <21>;
- sirf,uart-dma-tx-channel = <2>;
+ dmas = <&dmac1 5>, <&dmac0 2>;
+ dma-names = "rx", "tx";

and we move dma_request_channel() to dma_request_slave_channel(), we don't need to
call sirfsoc dma filter function sirfsoc_dma_filter_id() again.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13 10:36:25 -08:00
Qipan Li
fb78b81142 serial: sirf: fix kernel panic caused by unpaired spinlock
commit 8b9ade9f74 coming from Viresh Kumar "tty: serial: sirfsoc: drop
uart_port->lock before calling tty_flip_buffer_push()" broke sirfsoc uart
driver by knic:

	[    5.129122] BUG: spinlock already unlocked on CPU#0, ip6tables/1331
	[    5.132554]  lock: sirfsoc_uart_ports+0x4/0x8a0, .magic: dead4ead,
	.owner: <none>/-1, .owner_cpu: -1
	[    5.141651] CPU: 0 PID: 1331 Comm: ip6tables Tainted: G
	W  O 3.10.16 #3
	[    5.148866] [<c0013528>] (unwind_backtrace+0x0/0xe0) from
	[<c0010e70>] (show_stack+0x10/0x14)
	[    5.157362] [<c0010e70>] (show_stack+0x10/0x14) from
	[<c01a5e68>] (do_raw_spin_unlock+0x40/0xc8)
	[    5.166125] [<c01a5e68>] (do_raw_spin_unlock+0x40/0xc8) from
	[<c03ff8b4>] (_raw_spin_unlock+0x8/0x40)
	[    5.175322] [<c03ff8b4>] (_raw_spin_unlock+0x8/0x40) from
	[<c0203fcc>] (sirfsoc_uart_pio_rx_chars+0xa4/0xc0)
	[    5.185120] [<c0203fcc>]
	(sirfsoc_uart_pio_rx_chars+0xa4/0xc0) from [<c0204fb8>]
	(sirfsoc_rx_tmo_process_tl+0xdc/0x1e0)
	[    5.195875] [<c0204fb8>]
	(sirfsoc_rx_tmo_process_tl+0xdc/0x1e0) from [<c0024b50>]
	(tasklet_action+0x8c/0xec)
	[    5.205673] [<c0024b50>] (tasklet_action+0x8c/0xec) from
	[<c00242a8>] (__do_softirq+0xec/0x1d4)
	[    5.214347] [<c00242a8>] (__do_softirq+0xec/0x1d4) from
	[<c0024428>] (do_softirq+0x48/0x54)
	[    5.222674] [<c0024428>] (do_softirq+0x48/0x54) from
	[<c0024690>] (irq_exit+0x74/0xc0)
	[    5.230573] [<c0024690>] (irq_exit+0x74/0xc0) from
	[<c000e1e8>] (handle_IRQ+0x6c/0x90)
	[    5.238465] [<c000e1e8>] (handle_IRQ+0x6c/0x90) from
	[<c000d500>] (__irq_svc+0x40/0x70)
	[    5.246446] [<c000d500>] (__irq_svc+0x40/0x70) from
	[<c0092e7c>] (mark_page_accessed+0xc/0x68)
	[    5.255034] [<c0092e7c>] (mark_page_accessed+0xc/0x68) from
	[<c00a2a4c>] (unmap_single_vma+0x3bc/0x550)
	[    5.264402] [<c00a2a4c>] (unmap_single_vma+0x3bc/0x550) from
	[<c00a3b4c>] (unmap_vmas+0x44/0x54)
	[    5.273164] [<c00a3b4c>] (unmap_vmas+0x44/0x54) from
	[<c00a81a8>] (exit_mmap+0xc4/0x1e0)
	[    5.281233] [<c00a81a8>] (exit_mmap+0xc4/0x1e0) from
	[<c001bb78>] (mmput+0x3c/0xdc)
	[    5.288868] [<c001bb78>] (mmput+0x3c/0xdc) from [<c0021b0c>]
	(do_exit+0x30c/0x828)
	[    5.296413] [<c0021b0c>] (do_exit+0x30c/0x828) from
	[<c0022dac>] (do_group_exit+0x4c/0xb0)
	[    5.304653] [<c0022dac>] (do_group_exit+0x4c/0xb0) from
	[<c0022e20>] (__wake_up_parent+0x0/0x18)

Root cause:
the commit dropped uart_port->lock before calling tty_flip_buffer_push(), but in sirfsoc-uart,
sirfsoc_uart_pio_rx_chars() can be called by sirfsoc_rx_tmo_process_tl(). here uart_port->lock
has not been taken yet. so that caused unpaired lock/unlock.

Solution:
This patch is doing a quick fix for that, it adds spin_lock/unlock(&port->lock) protect to
sirfsoc_uart_pio_rx_chars() in sirfsoc_rx_tmo_process_tl() to keep spin_lock/unlock in pair.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Cc: stable <stable@vger.kernel.org> # 3.12
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13 10:02:19 -08:00
Qipan Li
df8d4aa0d8 serial: sirf: correct condition for fetching dma buffer into tty
In rx dma-callback it calls tasklet_schedule, if the tasklet
be scheduled after all the dma-callback in the rx dma channel,
current check condition in the tasklet will not do fetch dma
buffer into tty because tx_issued is equal with tx_completed,
so as timeout tasklet does.

so we check whether we should fetch the whole dma buffer into
tty according to the status of transactions in rx dma channel.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-07 17:09:04 -08:00
Qipan Li
388faf9ffd serial: sirf: provide pm entries of uart_ops
this patch provides PM entry of uart_ops, then drop clk enable and
disable because serial core will do it.

the patch also fixes the issue that uart hang in resume caused by
not-enabled clock.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-07 17:09:04 -08:00
Qipan Li
99e626f504 serial: sirf: use PM macro initialize PM functions
use SET_SYSTEM_SLEEP_PM_OPS to initialize suspend/resume functions
instead of legacy suspend and resume entries of platform_driver.
this will add hibernation support automatically as suspend to disk
entries are also set.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-07 17:09:04 -08:00
Qipan Li
59f8a62c25 serial: sirf: don't submit dma desc after timeout irqs occur
In rx timeout ISR and tasklet, we don't issue new dma desc as rx_done ISR
will do that.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 15:41:39 -07:00
Qipan Li
b60dfbae41 serial: sirf: fix the amount of serial ports
SiRFprimaII has three uart ports and three USP-based ports, so there
are totally six lines instead of five.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-27 16:25:44 -07:00
Qipan Li
459f15c45e serial: sirf: define macro for some magic numbers of USP
this patch clears some magic numbers for offset and bitshift
of USP registers.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-27 16:25:44 -07:00
Viresh Kumar
8b9ade9f74 tty: serial: sirfsoc: drop uart_port->lock before calling tty_flip_buffer_push()
The current driver triggers a lockdep warning for if tty_flip_buffer_push() is
called with uart_port->lock locked. This never shows up on UP kernels and comes
up only on SMP kernels.

Crash looks like this (produced with samsung.c driver):

-----
[<c0014d58>] (unwind_backtrace+0x0/0xf8) from [<c0011908>] (show_stack+0x10/0x14)
[<c0011908>] (show_stack+0x10/0x14) from [<c035da34>] (dump_stack+0x6c/0xac)
[<c035da34>] (dump_stack+0x6c/0xac) from [<c01b59ac>] (do_raw_spin_unlock+0xc4/0xd8)
[<c01b59ac>] (do_raw_spin_unlock+0xc4/0xd8) from [<c03627e4>] (_raw_spin_unlock_irqrestore+0xc/0)
[<c03627e4>] (_raw_spin_unlock_irqrestore+0xc/0x38) from [<c020a1a8>] (s3c24xx_serial_rx_chars+0)
[<c020a1a8>] (s3c24xx_serial_rx_chars+0x12c/0x260) from [<c020aae8>] (s3c64xx_serial_handle_irq+)
[<c020aae8>] (s3c64xx_serial_handle_irq+0x48/0x60) from [<c006aaa0>] (handle_irq_event_percpu+0x)
[<c006aaa0>] (handle_irq_event_percpu+0x50/0x194) from [<c006ac20>] (handle_irq_event+0x3c/0x5c)
[<c006ac20>] (handle_irq_event+0x3c/0x5c) from [<c006d864>] (handle_fasteoi_irq+0x80/0x13c)
[<c006d864>] (handle_fasteoi_irq+0x80/0x13c) from [<c006a4a4>] (generic_handle_irq+0x20/0x30)
[<c006a4a4>] (generic_handle_irq+0x20/0x30) from [<c000f454>] (handle_IRQ+0x38/0x94)
[<c000f454>] (handle_IRQ+0x38/0x94) from [<c0008538>] (gic_handle_irq+0x34/0x68)
[<c0008538>] (gic_handle_irq+0x34/0x68) from [<c00123c0>] (__irq_svc+0x40/0x70)
Exception stack(0xc04cdf70 to 0xc04cdfb8)
df60:                                     00000000 00000000 0000166e 00000000
df80: c04cc000 c050278f c050278f 00000001 c04d444c 410fc0f4 c03649b0 00000000
dfa0: 00000001 c04cdfb8 c000f758 c000f75c 60070013 ffffffff
[<c00123c0>] (__irq_svc+0x40/0x70) from [<c000f75c>] (arch_cpu_idle+0x28/0x30)
[<c000f75c>] (arch_cpu_idle+0x28/0x30) from [<c0054888>] (cpu_startup_entry+0x5c/0x148)
[<c0054888>] (cpu_startup_entry+0x5c/0x148) from [<c0497aa4>] (start_kernel+0x334/0x38c)
BUG: spinlock lockup suspected on CPU#0, kworker/0:1/360
 lock: s3c24xx_serial_ports+0x1d8/0x370, .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1
CPU: 0 PID: 360 Comm: kworker/0:1 Not tainted 3.11.0-rc6-next-20130819-00003-g75485f1 #2
Workqueue: events flush_to_ldisc
[<c0014d58>] (unwind_backtrace+0x0/0xf8) from [<c0011908>] (show_stack+0x10/0x14)
[<c0011908>] (show_stack+0x10/0x14) from [<c035da34>] (dump_stack+0x6c/0xac)
[<c035da34>] (dump_stack+0x6c/0xac) from [<c01b581c>] (do_raw_spin_lock+0x100/0x17c)
[<c01b581c>] (do_raw_spin_lock+0x100/0x17c) from [<c03628a0>] (_raw_spin_lock_irqsave+0x20/0x28)
[<c03628a0>] (_raw_spin_lock_irqsave+0x20/0x28) from [<c0203224>] (uart_start+0x18/0x34)
[<c0203224>] (uart_start+0x18/0x34) from [<c01ef890>] (__receive_buf+0x4b4/0x738)
[<c01ef890>] (__receive_buf+0x4b4/0x738) from [<c01efb44>] (n_tty_receive_buf2+0x30/0x98)
[<c01efb44>] (n_tty_receive_buf2+0x30/0x98) from [<c01f2ba8>] (flush_to_ldisc+0xec/0x138)
[<c01f2ba8>] (flush_to_ldisc+0xec/0x138) from [<c0031af0>] (process_one_work+0xfc/0x348)
[<c0031af0>] (process_one_work+0xfc/0x348) from [<c0032138>] (worker_thread+0x138/0x37c)
[<c0032138>] (worker_thread+0x138/0x37c) from [<c0037a7c>] (kthread+0xa4/0xb0)
[<c0037a7c>] (kthread+0xa4/0xb0) from [<c000e5f8>] (ret_from_fork+0x14/0x3c)
-----

Release the port lock before calling tty_flip_buffer_push() and reacquire it
after the call.

Similar stuff was already done for few other drivers in the past, like:

commit 2389b27216
Author: Thomas Gleixner <tglx@linutronix.de>
Date:   Tue May 29 21:53:50 2007 +0100

    [ARM] 4417/1: Serial: Fix AMBA drivers locking

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-27 16:17:35 -07:00
Qipan Li
8316d04c42 serial: sirf: add DMA support using dmaengine APIs
if we get the valid dma channels from dts, move to use dmaengine to do
rx/tx. because the dma hardware requires dma address and length to be
4bytes aligned, in this driver, we will still use PIO for non-aligned
bytes, and use dma for aligned bytes.

for rx, to keep the dmaengine always active, we use double-buffer, so
we issue two dma_desc at first, and maintain the status of both
1. dma transfer done: update in rx dma finish callback
2. dma buffer is inserted into tty: update in rx dma finish tasklet and
   rx timeout tasklet
so we re-issue the dma_desc only if both 1&2 are finished.

for tx, as we know the actual length for every transfer, we don't need
the above double buffering.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-19 17:13:22 -07:00
Qipan Li
15cdcb12cb serial: sirf: fix the namespace of startup_uart entry
startup_uart_controller() loses namespace, this patch
drops the function directly and move the content into
sirfsoc_uart_startup().

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-19 17:13:22 -07:00
Qipan Li
67bc306cec serial: sirf: fix the typo for rts/cts gpio
fix the typo in commit 2eb5618de8 which uses two
gpios for rts/cts.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-19 17:12:21 -07:00
Qipan Li
2eb5618de8 serial: sirf: fix the hardware-flow-ctrl for USP-based UART
for USP-based UART, we use two gpios as RTS and CST pins.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-14 18:33:08 -07:00
Barry Song
a343756e07 serial: sirf: drop redundant pinctrl_get_select_default as pinctrl core does it
pinctrl core will get default pinmux, so drop it in the sirfsoc serial driver.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-14 18:33:08 -07:00
Jingoo Han
ada1f443d1 serial: sirf: Staticize local symbols
These local symbols are used only in this file.
Fix the following sparse warnings:

drivers/tty/serial/sirfsoc_uart.c:147:6: warning: symbol 'sirfsoc_uart_start_tx' was not declared. Should it be static?
drivers/tty/serial/sirfsoc_uart.c:636:5: warning: symbol 'sirfsoc_uart_probe' was not declared. Should it be static?

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:32:48 -07:00
Qipan Li
5df831117b serial: sirf: make the driver also support USP-based UART
Universal Serial Ports (USP) can be used as PCM, UART, SPI,
I2S etc. this makes the USP work as UART. the basic work
flow is same with UART controller, the main difference will
be offset of registers and bits.

this patch makes the old sirfsoc uart driver support both
sirf UART and USP-based UART by making their differences
become private data.

Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:29:53 -07:00
Barry Song
909102db44 serial: sirf: add support for Marco chip
the marco and coming new CSR multiple SoCs have SET/CLR pair for
INTEN registers to avoid some read-modify-write.

this patch adds support for this and make the driver support current
up and coming mp SoCs.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:29:53 -07:00
Jingoo Han
43b829b3c1 serial: remove unnecessary platform_set_drvdata()
The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d06310
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Barry Song <baohua.song@csr.com>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 15:39:36 -07:00
Alexey Khoroshilov
9f6d20ff84 tty/serial/sirf: fix error propagation in sirfsoc_uart_probe()
If pinctrl_get_select_default() fails, sirfsoc_uart_probe()
returns IS_ERR(result) instead of PTR_ERR(result).

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-06 13:07:05 -07:00
Arnd Bergmann
45efcb2d32 tty/serial/sirf: fix MODULE_DEVICE_TABLE
This fixes building the sirfsorc-uart driver as a loadable module,
which uses an incorrect MODULE_DEVICE_TABLE, by changing the reference to the
correct symbol.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-23 10:43:18 -07:00
Barry Song
ac4ce71889 serial: sirf: only use lookup table to set baudrate when ioclk=150MHz
The fast lookup table to set baudrate is only right when ioclk
is 150MHz. for most platforms, ioclk is 150MHz, but some boards
might set ioclk to other frequency.

so re-calc the clk_div_reg when ioclk is not 150MHz. this patch
also gets clk in probe and puts it in remove.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-17 17:18:55 -08:00
Jiri Slaby
2e124b4a39 TTY: switch tty_flip_buffer_push
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:30:15 -08:00
Barry Song
5425e03f97 serial: sirf: add support for new SiRFmarco SMP SoC
CSR SiRFmarco's UART IP is same with SiRFprimaII except that
it has two more uart ports.
this patch makes the old driver support new SiRFmarco as well:
1. add .compatible = "sirf,marco-uart" to OF match table
2. add two ports in the port table
3. take spin_lock in isr to avoid the conflict of threads opening
uart on CPU1 and isr running on CPU0.
For 3, we did see some problems on SiRFmarco as SiRFmarco is a
SMP SoC but the old SiRFprimaII is UP.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 21:54:40 -08:00
Bill Pemberton
de88b34042 tty: remove use of __devinitdata
CONFIG_HOTPLUG is going away as an option so __devinitdata is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:25:06 -08:00
Bill Pemberton
2d47b71602 tty: serial: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Lucas Tavares <lucaskt@linux.vnet.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Tony Prisk <linux@prisktech.co.nz>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-21 15:19:52 -08:00
Julia Lawall
9250dd5738 drivers/tty/serial/sirfsoc_uart.c: drop frees of devm_ alloc'd data
devm free functions should not have to be explicitly used.

A semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
@@

(
* devm_kfree(...);
|
* devm_free_irq(...);
|
* devm_iounmap(...);
|
* devm_release_region(...);
|
* devm_release_mem_region(...);
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05 12:41:57 -07:00
Stephen Warren
6e5e959dde pinctrl: API changes to support multiple states per device
The API model is changed from:

p = pinctrl_get(dev, "state1");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);
p = pinctrl_get(dev, "state2");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);

to this:

p = pinctrl_get(dev);
s1 = pinctrl_lookup_state(p, "state1");
s2 = pinctrl_lookup_state(p, "state2");
pinctrl_select_state(p, s1);
...
pinctrl_select_state(p, s2);
...
pinctrl_put(p);

This allows devices to directly transition between states without
disabling the pin controller programming and put()/get()ing the
configuration data each time. This model will also better suit pinconf
programming, which doesn't have a concept of "disable".

The special-case hogging feature of pin controllers is re-written to use
the regular APIs instead of special-case code. Hence, the pinmux-hogs
debugfs file is removed; see the top-level pinctrl-handles files for
equivalent data.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-05 11:22:59 +01:00
Stephen Warren
110e4ec5a1 pinctrl: assume map table entries can't have a NULL name field
pinctrl_register_mappings() already requires that every mapping table
entry have a non-NULL name field.

Logically, this makes sense too; drivers should always request a specific
named state so they know what they're getting. Relying on getting the
first mentioned state in the mapping table is error-prone, and a nasty
special case to implement, given that a given the mapping table may define
multiple states for a device.

Remove a small part of the documentation that talked about optionally
requesting a specific state; it's mandatory now.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-02 16:20:54 +01:00
Linus Walleij
5c9bdc3f52 serial/sirf: fixup for changes to pin control
We changed the signature of the pin multiplexing functions to
handle any pin business, so fix up the Sirf driver to call this
new interface and rename some variables to make the semantics
understandable.

Cc: linux-serial@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22 17:59:12 +01:00
Rong Wang
161e773cbd UART: add CSR SiRFprimaII SoC on-chip uart drivers
SiRFprimaII is the latest generation application processor from CSR’s
multi-function SoC product family.
The SoC support codes are in arch/arm/mach-prima2 from Linux mainline
3.0.

There are three dedicated UARTs in system. This patch adds basic driver
support for them.

It has used the newest pinmux subsystem from Linus Walleij.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rong Wang <Rong.Wang@csr.com>
Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-17 11:46:04 -08:00