xref: /linux/drivers/tty/serial/pch_uart.c (revision 045ddc8991698a8e9c5668c6190faa8b5d516dc0)
1 /*
2  *Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
3  *
4  *This program is free software; you can redistribute it and/or modify
5  *it under the terms of the GNU General Public License as published by
6  *the Free Software Foundation; version 2 of the License.
7  *
8  *This program is distributed in the hope that it will be useful,
9  *but WITHOUT ANY WARRANTY; without even the implied warranty of
10  *MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  *GNU General Public License for more details.
12  *
13  *You should have received a copy of the GNU General Public License
14  *along with this program; if not, write to the Free Software
15  *Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
16  */
17 #include <linux/kernel.h>
18 #include <linux/serial_reg.h>
19 #include <linux/slab.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/serial_core.h>
23 #include <linux/tty.h>
24 #include <linux/tty_flip.h>
25 #include <linux/interrupt.h>
26 #include <linux/io.h>
27 #include <linux/dmi.h>
28 
29 #include <linux/dmaengine.h>
30 #include <linux/pch_dma.h>
31 
32 enum {
33 	PCH_UART_HANDLED_RX_INT_SHIFT,
34 	PCH_UART_HANDLED_TX_INT_SHIFT,
35 	PCH_UART_HANDLED_RX_ERR_INT_SHIFT,
36 	PCH_UART_HANDLED_RX_TRG_INT_SHIFT,
37 	PCH_UART_HANDLED_MS_INT_SHIFT,
38 };
39 
40 enum {
41 	PCH_UART_8LINE,
42 	PCH_UART_2LINE,
43 };
44 
45 #define PCH_UART_DRIVER_DEVICE "ttyPCH"
46 
47 /* Set the max number of UART port
48  * Intel EG20T PCH: 4 port
49  * LAPIS Semiconductor ML7213 IOH: 3 port
50  * LAPIS Semiconductor ML7223 IOH: 2 port
51 */
52 #define PCH_UART_NR	4
53 
54 #define PCH_UART_HANDLED_RX_INT	(1<<((PCH_UART_HANDLED_RX_INT_SHIFT)<<1))
55 #define PCH_UART_HANDLED_TX_INT	(1<<((PCH_UART_HANDLED_TX_INT_SHIFT)<<1))
56 #define PCH_UART_HANDLED_RX_ERR_INT	(1<<((\
57 					PCH_UART_HANDLED_RX_ERR_INT_SHIFT)<<1))
58 #define PCH_UART_HANDLED_RX_TRG_INT	(1<<((\
59 					PCH_UART_HANDLED_RX_TRG_INT_SHIFT)<<1))
60 #define PCH_UART_HANDLED_MS_INT	(1<<((PCH_UART_HANDLED_MS_INT_SHIFT)<<1))
61 
62 #define PCH_UART_RBR		0x00
63 #define PCH_UART_THR		0x00
64 
65 #define PCH_UART_IER_MASK	(PCH_UART_IER_ERBFI|PCH_UART_IER_ETBEI|\
66 				PCH_UART_IER_ELSI|PCH_UART_IER_EDSSI)
67 #define PCH_UART_IER_ERBFI	0x00000001
68 #define PCH_UART_IER_ETBEI	0x00000002
69 #define PCH_UART_IER_ELSI	0x00000004
70 #define PCH_UART_IER_EDSSI	0x00000008
71 
72 #define PCH_UART_IIR_IP			0x00000001
73 #define PCH_UART_IIR_IID		0x00000006
74 #define PCH_UART_IIR_MSI		0x00000000
75 #define PCH_UART_IIR_TRI		0x00000002
76 #define PCH_UART_IIR_RRI		0x00000004
77 #define PCH_UART_IIR_REI		0x00000006
78 #define PCH_UART_IIR_TOI		0x00000008
79 #define PCH_UART_IIR_FIFO256		0x00000020
80 #define PCH_UART_IIR_FIFO64		PCH_UART_IIR_FIFO256
81 #define PCH_UART_IIR_FE			0x000000C0
82 
83 #define PCH_UART_FCR_FIFOE		0x00000001
84 #define PCH_UART_FCR_RFR		0x00000002
85 #define PCH_UART_FCR_TFR		0x00000004
86 #define PCH_UART_FCR_DMS		0x00000008
87 #define PCH_UART_FCR_FIFO256		0x00000020
88 #define PCH_UART_FCR_RFTL		0x000000C0
89 
90 #define PCH_UART_FCR_RFTL1		0x00000000
91 #define PCH_UART_FCR_RFTL64		0x00000040
92 #define PCH_UART_FCR_RFTL128		0x00000080
93 #define PCH_UART_FCR_RFTL224		0x000000C0
94 #define PCH_UART_FCR_RFTL16		PCH_UART_FCR_RFTL64
95 #define PCH_UART_FCR_RFTL32		PCH_UART_FCR_RFTL128
96 #define PCH_UART_FCR_RFTL56		PCH_UART_FCR_RFTL224
97 #define PCH_UART_FCR_RFTL4		PCH_UART_FCR_RFTL64
98 #define PCH_UART_FCR_RFTL8		PCH_UART_FCR_RFTL128
99 #define PCH_UART_FCR_RFTL14		PCH_UART_FCR_RFTL224
100 #define PCH_UART_FCR_RFTL_SHIFT		6
101 
102 #define PCH_UART_LCR_WLS	0x00000003
103 #define PCH_UART_LCR_STB	0x00000004
104 #define PCH_UART_LCR_PEN	0x00000008
105 #define PCH_UART_LCR_EPS	0x00000010
106 #define PCH_UART_LCR_SP		0x00000020
107 #define PCH_UART_LCR_SB		0x00000040
108 #define PCH_UART_LCR_DLAB	0x00000080
109 #define PCH_UART_LCR_NP		0x00000000
110 #define PCH_UART_LCR_OP		PCH_UART_LCR_PEN
111 #define PCH_UART_LCR_EP		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS)
112 #define PCH_UART_LCR_1P		(PCH_UART_LCR_PEN | PCH_UART_LCR_SP)
113 #define PCH_UART_LCR_0P		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS |\
114 				PCH_UART_LCR_SP)
115 
116 #define PCH_UART_LCR_5BIT	0x00000000
117 #define PCH_UART_LCR_6BIT	0x00000001
118 #define PCH_UART_LCR_7BIT	0x00000002
119 #define PCH_UART_LCR_8BIT	0x00000003
120 
121 #define PCH_UART_MCR_DTR	0x00000001
122 #define PCH_UART_MCR_RTS	0x00000002
123 #define PCH_UART_MCR_OUT	0x0000000C
124 #define PCH_UART_MCR_LOOP	0x00000010
125 #define PCH_UART_MCR_AFE	0x00000020
126 
127 #define PCH_UART_LSR_DR		0x00000001
128 #define PCH_UART_LSR_ERR	(1<<7)
129 
130 #define PCH_UART_MSR_DCTS	0x00000001
131 #define PCH_UART_MSR_DDSR	0x00000002
132 #define PCH_UART_MSR_TERI	0x00000004
133 #define PCH_UART_MSR_DDCD	0x00000008
134 #define PCH_UART_MSR_CTS	0x00000010
135 #define PCH_UART_MSR_DSR	0x00000020
136 #define PCH_UART_MSR_RI		0x00000040
137 #define PCH_UART_MSR_DCD	0x00000080
138 #define PCH_UART_MSR_DELTA	(PCH_UART_MSR_DCTS | PCH_UART_MSR_DDSR |\
139 				PCH_UART_MSR_TERI | PCH_UART_MSR_DDCD)
140 
141 #define PCH_UART_DLL		0x00
142 #define PCH_UART_DLM		0x01
143 
144 #define PCH_UART_IID_RLS	(PCH_UART_IIR_REI)
145 #define PCH_UART_IID_RDR	(PCH_UART_IIR_RRI)
146 #define PCH_UART_IID_RDR_TO	(PCH_UART_IIR_RRI | PCH_UART_IIR_TOI)
147 #define PCH_UART_IID_THRE	(PCH_UART_IIR_TRI)
148 #define PCH_UART_IID_MS		(PCH_UART_IIR_MSI)
149 
150 #define PCH_UART_HAL_PARITY_NONE	(PCH_UART_LCR_NP)
151 #define PCH_UART_HAL_PARITY_ODD		(PCH_UART_LCR_OP)
152 #define PCH_UART_HAL_PARITY_EVEN	(PCH_UART_LCR_EP)
153 #define PCH_UART_HAL_PARITY_FIX1	(PCH_UART_LCR_1P)
154 #define PCH_UART_HAL_PARITY_FIX0	(PCH_UART_LCR_0P)
155 #define PCH_UART_HAL_5BIT		(PCH_UART_LCR_5BIT)
156 #define PCH_UART_HAL_6BIT		(PCH_UART_LCR_6BIT)
157 #define PCH_UART_HAL_7BIT		(PCH_UART_LCR_7BIT)
158 #define PCH_UART_HAL_8BIT		(PCH_UART_LCR_8BIT)
159 #define PCH_UART_HAL_STB1		0
160 #define PCH_UART_HAL_STB2		(PCH_UART_LCR_STB)
161 
162 #define PCH_UART_HAL_CLR_TX_FIFO	(PCH_UART_FCR_TFR)
163 #define PCH_UART_HAL_CLR_RX_FIFO	(PCH_UART_FCR_RFR)
164 #define PCH_UART_HAL_CLR_ALL_FIFO	(PCH_UART_HAL_CLR_TX_FIFO | \
165 					PCH_UART_HAL_CLR_RX_FIFO)
166 
167 #define PCH_UART_HAL_DMA_MODE0		0
168 #define PCH_UART_HAL_FIFO_DIS		0
169 #define PCH_UART_HAL_FIFO16		(PCH_UART_FCR_FIFOE)
170 #define PCH_UART_HAL_FIFO256		(PCH_UART_FCR_FIFOE | \
171 					PCH_UART_FCR_FIFO256)
172 #define PCH_UART_HAL_FIFO64		(PCH_UART_HAL_FIFO256)
173 #define PCH_UART_HAL_TRIGGER1		(PCH_UART_FCR_RFTL1)
174 #define PCH_UART_HAL_TRIGGER64		(PCH_UART_FCR_RFTL64)
175 #define PCH_UART_HAL_TRIGGER128		(PCH_UART_FCR_RFTL128)
176 #define PCH_UART_HAL_TRIGGER224		(PCH_UART_FCR_RFTL224)
177 #define PCH_UART_HAL_TRIGGER16		(PCH_UART_FCR_RFTL16)
178 #define PCH_UART_HAL_TRIGGER32		(PCH_UART_FCR_RFTL32)
179 #define PCH_UART_HAL_TRIGGER56		(PCH_UART_FCR_RFTL56)
180 #define PCH_UART_HAL_TRIGGER4		(PCH_UART_FCR_RFTL4)
181 #define PCH_UART_HAL_TRIGGER8		(PCH_UART_FCR_RFTL8)
182 #define PCH_UART_HAL_TRIGGER14		(PCH_UART_FCR_RFTL14)
183 #define PCH_UART_HAL_TRIGGER_L		(PCH_UART_FCR_RFTL64)
184 #define PCH_UART_HAL_TRIGGER_M		(PCH_UART_FCR_RFTL128)
185 #define PCH_UART_HAL_TRIGGER_H		(PCH_UART_FCR_RFTL224)
186 
187 #define PCH_UART_HAL_RX_INT		(PCH_UART_IER_ERBFI)
188 #define PCH_UART_HAL_TX_INT		(PCH_UART_IER_ETBEI)
189 #define PCH_UART_HAL_RX_ERR_INT		(PCH_UART_IER_ELSI)
190 #define PCH_UART_HAL_MS_INT		(PCH_UART_IER_EDSSI)
191 #define PCH_UART_HAL_ALL_INT		(PCH_UART_IER_MASK)
192 
193 #define PCH_UART_HAL_DTR		(PCH_UART_MCR_DTR)
194 #define PCH_UART_HAL_RTS		(PCH_UART_MCR_RTS)
195 #define PCH_UART_HAL_OUT		(PCH_UART_MCR_OUT)
196 #define PCH_UART_HAL_LOOP		(PCH_UART_MCR_LOOP)
197 #define PCH_UART_HAL_AFE		(PCH_UART_MCR_AFE)
198 
199 #define PCI_VENDOR_ID_ROHM		0x10DB
200 
201 struct pch_uart_buffer {
202 	unsigned char *buf;
203 	int size;
204 };
205 
206 struct eg20t_port {
207 	struct uart_port port;
208 	int port_type;
209 	void __iomem *membase;
210 	resource_size_t mapbase;
211 	unsigned int iobase;
212 	struct pci_dev *pdev;
213 	int fifo_size;
214 	int base_baud;
215 	int start_tx;
216 	int start_rx;
217 	int tx_empty;
218 	int int_dis_flag;
219 	int trigger;
220 	int trigger_level;
221 	struct pch_uart_buffer rxbuf;
222 	unsigned int dmsr;
223 	unsigned int fcr;
224 	unsigned int mcr;
225 	unsigned int use_dma;
226 	unsigned int use_dma_flag;
227 	struct dma_async_tx_descriptor	*desc_tx;
228 	struct dma_async_tx_descriptor	*desc_rx;
229 	struct pch_dma_slave		param_tx;
230 	struct pch_dma_slave		param_rx;
231 	struct dma_chan			*chan_tx;
232 	struct dma_chan			*chan_rx;
233 	struct scatterlist		*sg_tx_p;
234 	int				nent;
235 	struct scatterlist		sg_rx;
236 	int				tx_dma_use;
237 	void				*rx_buf_virt;
238 	dma_addr_t			rx_buf_dma;
239 };
240 
241 /**
242  * struct pch_uart_driver_data - private data structure for UART-DMA
243  * @port_type:			The number of DMA channel
244  * @line_no:			UART port line number (0, 1, 2...)
245  */
246 struct pch_uart_driver_data {
247 	int port_type;
248 	int line_no;
249 };
250 
251 enum pch_uart_num_t {
252 	pch_et20t_uart0 = 0,
253 	pch_et20t_uart1,
254 	pch_et20t_uart2,
255 	pch_et20t_uart3,
256 	pch_ml7213_uart0,
257 	pch_ml7213_uart1,
258 	pch_ml7213_uart2,
259 	pch_ml7223_uart0,
260 	pch_ml7223_uart1,
261 	pch_ml7831_uart0,
262 	pch_ml7831_uart1,
263 };
264 
265 static struct pch_uart_driver_data drv_dat[] = {
266 	[pch_et20t_uart0] = {PCH_UART_8LINE, 0},
267 	[pch_et20t_uart1] = {PCH_UART_2LINE, 1},
268 	[pch_et20t_uart2] = {PCH_UART_2LINE, 2},
269 	[pch_et20t_uart3] = {PCH_UART_2LINE, 3},
270 	[pch_ml7213_uart0] = {PCH_UART_8LINE, 0},
271 	[pch_ml7213_uart1] = {PCH_UART_2LINE, 1},
272 	[pch_ml7213_uart2] = {PCH_UART_2LINE, 2},
273 	[pch_ml7223_uart0] = {PCH_UART_8LINE, 0},
274 	[pch_ml7223_uart1] = {PCH_UART_2LINE, 1},
275 	[pch_ml7831_uart0] = {PCH_UART_8LINE, 0},
276 	[pch_ml7831_uart1] = {PCH_UART_2LINE, 1},
277 };
278 
279 static unsigned int default_baud = 9600;
280 static const int trigger_level_256[4] = { 1, 64, 128, 224 };
281 static const int trigger_level_64[4] = { 1, 16, 32, 56 };
282 static const int trigger_level_16[4] = { 1, 4, 8, 14 };
283 static const int trigger_level_1[4] = { 1, 1, 1, 1 };
284 
285 static void pch_uart_hal_request(struct pci_dev *pdev, int fifosize,
286 				 int base_baud)
287 {
288 	struct eg20t_port *priv = pci_get_drvdata(pdev);
289 
290 	priv->trigger_level = 1;
291 	priv->fcr = 0;
292 }
293 
294 static unsigned int get_msr(struct eg20t_port *priv, void __iomem *base)
295 {
296 	unsigned int msr = ioread8(base + UART_MSR);
297 	priv->dmsr |= msr & PCH_UART_MSR_DELTA;
298 
299 	return msr;
300 }
301 
302 static void pch_uart_hal_enable_interrupt(struct eg20t_port *priv,
303 					  unsigned int flag)
304 {
305 	u8 ier = ioread8(priv->membase + UART_IER);
306 	ier |= flag & PCH_UART_IER_MASK;
307 	iowrite8(ier, priv->membase + UART_IER);
308 }
309 
310 static void pch_uart_hal_disable_interrupt(struct eg20t_port *priv,
311 					   unsigned int flag)
312 {
313 	u8 ier = ioread8(priv->membase + UART_IER);
314 	ier &= ~(flag & PCH_UART_IER_MASK);
315 	iowrite8(ier, priv->membase + UART_IER);
316 }
317 
318 static int pch_uart_hal_set_line(struct eg20t_port *priv, int baud,
319 				 unsigned int parity, unsigned int bits,
320 				 unsigned int stb)
321 {
322 	unsigned int dll, dlm, lcr;
323 	int div;
324 
325 	div = DIV_ROUND_CLOSEST(priv->base_baud / 16, baud);
326 	if (div < 0 || USHRT_MAX <= div) {
327 		dev_err(priv->port.dev, "Invalid Baud(div=0x%x)\n", div);
328 		return -EINVAL;
329 	}
330 
331 	dll = (unsigned int)div & 0x00FFU;
332 	dlm = ((unsigned int)div >> 8) & 0x00FFU;
333 
334 	if (parity & ~(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS | PCH_UART_LCR_SP)) {
335 		dev_err(priv->port.dev, "Invalid parity(0x%x)\n", parity);
336 		return -EINVAL;
337 	}
338 
339 	if (bits & ~PCH_UART_LCR_WLS) {
340 		dev_err(priv->port.dev, "Invalid bits(0x%x)\n", bits);
341 		return -EINVAL;
342 	}
343 
344 	if (stb & ~PCH_UART_LCR_STB) {
345 		dev_err(priv->port.dev, "Invalid STB(0x%x)\n", stb);
346 		return -EINVAL;
347 	}
348 
349 	lcr = parity;
350 	lcr |= bits;
351 	lcr |= stb;
352 
353 	dev_dbg(priv->port.dev, "%s:baud = %d, div = %04x, lcr = %02x (%lu)\n",
354 		 __func__, baud, div, lcr, jiffies);
355 	iowrite8(PCH_UART_LCR_DLAB, priv->membase + UART_LCR);
356 	iowrite8(dll, priv->membase + PCH_UART_DLL);
357 	iowrite8(dlm, priv->membase + PCH_UART_DLM);
358 	iowrite8(lcr, priv->membase + UART_LCR);
359 
360 	return 0;
361 }
362 
363 static int pch_uart_hal_fifo_reset(struct eg20t_port *priv,
364 				    unsigned int flag)
365 {
366 	if (flag & ~(PCH_UART_FCR_TFR | PCH_UART_FCR_RFR)) {
367 		dev_err(priv->port.dev, "%s:Invalid flag(0x%x)\n",
368 			__func__, flag);
369 		return -EINVAL;
370 	}
371 
372 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr, priv->membase + UART_FCR);
373 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr | flag,
374 		 priv->membase + UART_FCR);
375 	iowrite8(priv->fcr, priv->membase + UART_FCR);
376 
377 	return 0;
378 }
379 
380 static int pch_uart_hal_set_fifo(struct eg20t_port *priv,
381 				 unsigned int dmamode,
382 				 unsigned int fifo_size, unsigned int trigger)
383 {
384 	u8 fcr;
385 
386 	if (dmamode & ~PCH_UART_FCR_DMS) {
387 		dev_err(priv->port.dev, "%s:Invalid DMA Mode(0x%x)\n",
388 			__func__, dmamode);
389 		return -EINVAL;
390 	}
391 
392 	if (fifo_size & ~(PCH_UART_FCR_FIFOE | PCH_UART_FCR_FIFO256)) {
393 		dev_err(priv->port.dev, "%s:Invalid FIFO SIZE(0x%x)\n",
394 			__func__, fifo_size);
395 		return -EINVAL;
396 	}
397 
398 	if (trigger & ~PCH_UART_FCR_RFTL) {
399 		dev_err(priv->port.dev, "%s:Invalid TRIGGER(0x%x)\n",
400 			__func__, trigger);
401 		return -EINVAL;
402 	}
403 
404 	switch (priv->fifo_size) {
405 	case 256:
406 		priv->trigger_level =
407 		    trigger_level_256[trigger >> PCH_UART_FCR_RFTL_SHIFT];
408 		break;
409 	case 64:
410 		priv->trigger_level =
411 		    trigger_level_64[trigger >> PCH_UART_FCR_RFTL_SHIFT];
412 		break;
413 	case 16:
414 		priv->trigger_level =
415 		    trigger_level_16[trigger >> PCH_UART_FCR_RFTL_SHIFT];
416 		break;
417 	default:
418 		priv->trigger_level =
419 		    trigger_level_1[trigger >> PCH_UART_FCR_RFTL_SHIFT];
420 		break;
421 	}
422 	fcr =
423 	    dmamode | fifo_size | trigger | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR;
424 	iowrite8(PCH_UART_FCR_FIFOE, priv->membase + UART_FCR);
425 	iowrite8(PCH_UART_FCR_FIFOE | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR,
426 		 priv->membase + UART_FCR);
427 	iowrite8(fcr, priv->membase + UART_FCR);
428 	priv->fcr = fcr;
429 
430 	return 0;
431 }
432 
433 static u8 pch_uart_hal_get_modem(struct eg20t_port *priv)
434 {
435 	priv->dmsr = 0;
436 	return get_msr(priv, priv->membase);
437 }
438 
439 static void pch_uart_hal_write(struct eg20t_port *priv,
440 			      const unsigned char *buf, int tx_size)
441 {
442 	int i;
443 	unsigned int thr;
444 
445 	for (i = 0; i < tx_size;) {
446 		thr = buf[i++];
447 		iowrite8(thr, priv->membase + PCH_UART_THR);
448 	}
449 }
450 
451 static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
452 			     int rx_size)
453 {
454 	int i;
455 	u8 rbr, lsr;
456 
457 	lsr = ioread8(priv->membase + UART_LSR);
458 	for (i = 0, lsr = ioread8(priv->membase + UART_LSR);
459 	     i < rx_size && lsr & UART_LSR_DR;
460 	     lsr = ioread8(priv->membase + UART_LSR)) {
461 		rbr = ioread8(priv->membase + PCH_UART_RBR);
462 		buf[i++] = rbr;
463 	}
464 	return i;
465 }
466 
467 static unsigned int pch_uart_hal_get_iid(struct eg20t_port *priv)
468 {
469 	unsigned int iir;
470 	int ret;
471 
472 	iir = ioread8(priv->membase + UART_IIR);
473 	ret = (iir & (PCH_UART_IIR_IID | PCH_UART_IIR_TOI | PCH_UART_IIR_IP));
474 	return ret;
475 }
476 
477 static u8 pch_uart_hal_get_line_status(struct eg20t_port *priv)
478 {
479 	return ioread8(priv->membase + UART_LSR);
480 }
481 
482 static void pch_uart_hal_set_break(struct eg20t_port *priv, int on)
483 {
484 	unsigned int lcr;
485 
486 	lcr = ioread8(priv->membase + UART_LCR);
487 	if (on)
488 		lcr |= PCH_UART_LCR_SB;
489 	else
490 		lcr &= ~PCH_UART_LCR_SB;
491 
492 	iowrite8(lcr, priv->membase + UART_LCR);
493 }
494 
495 static int push_rx(struct eg20t_port *priv, const unsigned char *buf,
496 		   int size)
497 {
498 	struct uart_port *port;
499 	struct tty_struct *tty;
500 
501 	port = &priv->port;
502 	tty = tty_port_tty_get(&port->state->port);
503 	if (!tty) {
504 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
505 		return -EBUSY;
506 	}
507 
508 	tty_insert_flip_string(tty, buf, size);
509 	tty_flip_buffer_push(tty);
510 	tty_kref_put(tty);
511 
512 	return 0;
513 }
514 
515 static int pop_tx_x(struct eg20t_port *priv, unsigned char *buf)
516 {
517 	int ret;
518 	struct uart_port *port = &priv->port;
519 
520 	if (port->x_char) {
521 		dev_dbg(priv->port.dev, "%s:X character send %02x (%lu)\n",
522 			__func__, port->x_char, jiffies);
523 		buf[0] = port->x_char;
524 		port->x_char = 0;
525 		ret = 1;
526 	} else {
527 		ret = 0;
528 	}
529 
530 	return ret;
531 }
532 
533 static int dma_push_rx(struct eg20t_port *priv, int size)
534 {
535 	struct tty_struct *tty;
536 	int room;
537 	struct uart_port *port = &priv->port;
538 
539 	port = &priv->port;
540 	tty = tty_port_tty_get(&port->state->port);
541 	if (!tty) {
542 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
543 		return 0;
544 	}
545 
546 	room = tty_buffer_request_room(tty, size);
547 
548 	if (room < size)
549 		dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
550 			 size - room);
551 	if (!room)
552 		return room;
553 
554 	tty_insert_flip_string(tty, sg_virt(&priv->sg_rx), size);
555 
556 	port->icount.rx += room;
557 	tty_kref_put(tty);
558 
559 	return room;
560 }
561 
562 static void pch_free_dma(struct uart_port *port)
563 {
564 	struct eg20t_port *priv;
565 	priv = container_of(port, struct eg20t_port, port);
566 
567 	if (priv->chan_tx) {
568 		dma_release_channel(priv->chan_tx);
569 		priv->chan_tx = NULL;
570 	}
571 	if (priv->chan_rx) {
572 		dma_release_channel(priv->chan_rx);
573 		priv->chan_rx = NULL;
574 	}
575 	if (sg_dma_address(&priv->sg_rx))
576 		dma_free_coherent(port->dev, port->fifosize,
577 				  sg_virt(&priv->sg_rx),
578 				  sg_dma_address(&priv->sg_rx));
579 
580 	return;
581 }
582 
583 static bool filter(struct dma_chan *chan, void *slave)
584 {
585 	struct pch_dma_slave *param = slave;
586 
587 	if ((chan->chan_id == param->chan_id) && (param->dma_dev ==
588 						  chan->device->dev)) {
589 		chan->private = param;
590 		return true;
591 	} else {
592 		return false;
593 	}
594 }
595 
596 static void pch_request_dma(struct uart_port *port)
597 {
598 	dma_cap_mask_t mask;
599 	struct dma_chan *chan;
600 	struct pci_dev *dma_dev;
601 	struct pch_dma_slave *param;
602 	struct eg20t_port *priv =
603 				container_of(port, struct eg20t_port, port);
604 	dma_cap_zero(mask);
605 	dma_cap_set(DMA_SLAVE, mask);
606 
607 	dma_dev = pci_get_bus_and_slot(priv->pdev->bus->number,
608 				       PCI_DEVFN(0xa, 0)); /* Get DMA's dev
609 								information */
610 	/* Set Tx DMA */
611 	param = &priv->param_tx;
612 	param->dma_dev = &dma_dev->dev;
613 	param->chan_id = priv->port.line * 2; /* Tx = 0, 2, 4, ... */
614 
615 	param->tx_reg = port->mapbase + UART_TX;
616 	chan = dma_request_channel(mask, filter, param);
617 	if (!chan) {
618 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Tx)\n",
619 			__func__);
620 		return;
621 	}
622 	priv->chan_tx = chan;
623 
624 	/* Set Rx DMA */
625 	param = &priv->param_rx;
626 	param->dma_dev = &dma_dev->dev;
627 	param->chan_id = priv->port.line * 2 + 1; /* Rx = Tx + 1 */
628 
629 	param->rx_reg = port->mapbase + UART_RX;
630 	chan = dma_request_channel(mask, filter, param);
631 	if (!chan) {
632 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Rx)\n",
633 			__func__);
634 		dma_release_channel(priv->chan_tx);
635 		priv->chan_tx = NULL;
636 		return;
637 	}
638 
639 	/* Get Consistent memory for DMA */
640 	priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize,
641 				    &priv->rx_buf_dma, GFP_KERNEL);
642 	priv->chan_rx = chan;
643 }
644 
645 static void pch_dma_rx_complete(void *arg)
646 {
647 	struct eg20t_port *priv = arg;
648 	struct uart_port *port = &priv->port;
649 	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
650 	int count;
651 
652 	if (!tty) {
653 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
654 		return;
655 	}
656 
657 	dma_sync_sg_for_cpu(port->dev, &priv->sg_rx, 1, DMA_FROM_DEVICE);
658 	count = dma_push_rx(priv, priv->trigger_level);
659 	if (count)
660 		tty_flip_buffer_push(tty);
661 	tty_kref_put(tty);
662 	async_tx_ack(priv->desc_rx);
663 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
664 }
665 
666 static void pch_dma_tx_complete(void *arg)
667 {
668 	struct eg20t_port *priv = arg;
669 	struct uart_port *port = &priv->port;
670 	struct circ_buf *xmit = &port->state->xmit;
671 	struct scatterlist *sg = priv->sg_tx_p;
672 	int i;
673 
674 	for (i = 0; i < priv->nent; i++, sg++) {
675 		xmit->tail += sg_dma_len(sg);
676 		port->icount.tx += sg_dma_len(sg);
677 	}
678 	xmit->tail &= UART_XMIT_SIZE - 1;
679 	async_tx_ack(priv->desc_tx);
680 	dma_unmap_sg(port->dev, sg, priv->nent, DMA_TO_DEVICE);
681 	priv->tx_dma_use = 0;
682 	priv->nent = 0;
683 	kfree(priv->sg_tx_p);
684 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
685 }
686 
687 static int pop_tx(struct eg20t_port *priv, int size)
688 {
689 	int count = 0;
690 	struct uart_port *port = &priv->port;
691 	struct circ_buf *xmit = &port->state->xmit;
692 
693 	if (uart_tx_stopped(port) || uart_circ_empty(xmit) || count >= size)
694 		goto pop_tx_end;
695 
696 	do {
697 		int cnt_to_end =
698 		    CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
699 		int sz = min(size - count, cnt_to_end);
700 		pch_uart_hal_write(priv, &xmit->buf[xmit->tail], sz);
701 		xmit->tail = (xmit->tail + sz) & (UART_XMIT_SIZE - 1);
702 		count += sz;
703 	} while (!uart_circ_empty(xmit) && count < size);
704 
705 pop_tx_end:
706 	dev_dbg(priv->port.dev, "%d characters. Remained %d characters.(%lu)\n",
707 		 count, size - count, jiffies);
708 
709 	return count;
710 }
711 
712 static int handle_rx_to(struct eg20t_port *priv)
713 {
714 	struct pch_uart_buffer *buf;
715 	int rx_size;
716 	int ret;
717 	if (!priv->start_rx) {
718 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
719 		return 0;
720 	}
721 	buf = &priv->rxbuf;
722 	do {
723 		rx_size = pch_uart_hal_read(priv, buf->buf, buf->size);
724 		ret = push_rx(priv, buf->buf, rx_size);
725 		if (ret)
726 			return 0;
727 	} while (rx_size == buf->size);
728 
729 	return PCH_UART_HANDLED_RX_INT;
730 }
731 
732 static int handle_rx(struct eg20t_port *priv)
733 {
734 	return handle_rx_to(priv);
735 }
736 
737 static int dma_handle_rx(struct eg20t_port *priv)
738 {
739 	struct uart_port *port = &priv->port;
740 	struct dma_async_tx_descriptor *desc;
741 	struct scatterlist *sg;
742 
743 	priv = container_of(port, struct eg20t_port, port);
744 	sg = &priv->sg_rx;
745 
746 	sg_init_table(&priv->sg_rx, 1); /* Initialize SG table */
747 
748 	sg_dma_len(sg) = priv->trigger_level;
749 
750 	sg_set_page(&priv->sg_rx, virt_to_page(priv->rx_buf_virt),
751 		     sg_dma_len(sg), (unsigned long)priv->rx_buf_virt &
752 		     ~PAGE_MASK);
753 
754 	sg_dma_address(sg) = priv->rx_buf_dma;
755 
756 	desc = priv->chan_rx->device->device_prep_slave_sg(priv->chan_rx,
757 			sg, 1, DMA_FROM_DEVICE,
758 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
759 
760 	if (!desc)
761 		return 0;
762 
763 	priv->desc_rx = desc;
764 	desc->callback = pch_dma_rx_complete;
765 	desc->callback_param = priv;
766 	desc->tx_submit(desc);
767 	dma_async_issue_pending(priv->chan_rx);
768 
769 	return PCH_UART_HANDLED_RX_INT;
770 }
771 
772 static unsigned int handle_tx(struct eg20t_port *priv)
773 {
774 	struct uart_port *port = &priv->port;
775 	struct circ_buf *xmit = &port->state->xmit;
776 	int fifo_size;
777 	int tx_size;
778 	int size;
779 	int tx_empty;
780 
781 	if (!priv->start_tx) {
782 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
783 			__func__, jiffies);
784 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
785 		priv->tx_empty = 1;
786 		return 0;
787 	}
788 
789 	fifo_size = max(priv->fifo_size, 1);
790 	tx_empty = 1;
791 	if (pop_tx_x(priv, xmit->buf)) {
792 		pch_uart_hal_write(priv, xmit->buf, 1);
793 		port->icount.tx++;
794 		tx_empty = 0;
795 		fifo_size--;
796 	}
797 	size = min(xmit->head - xmit->tail, fifo_size);
798 	if (size < 0)
799 		size = fifo_size;
800 
801 	tx_size = pop_tx(priv, size);
802 	if (tx_size > 0) {
803 		port->icount.tx += tx_size;
804 		tx_empty = 0;
805 	}
806 
807 	priv->tx_empty = tx_empty;
808 
809 	if (tx_empty) {
810 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
811 		uart_write_wakeup(port);
812 	}
813 
814 	return PCH_UART_HANDLED_TX_INT;
815 }
816 
817 static unsigned int dma_handle_tx(struct eg20t_port *priv)
818 {
819 	struct uart_port *port = &priv->port;
820 	struct circ_buf *xmit = &port->state->xmit;
821 	struct scatterlist *sg;
822 	int nent;
823 	int fifo_size;
824 	int tx_empty;
825 	struct dma_async_tx_descriptor *desc;
826 	int num;
827 	int i;
828 	int bytes;
829 	int size;
830 	int rem;
831 
832 	if (!priv->start_tx) {
833 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
834 			__func__, jiffies);
835 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
836 		priv->tx_empty = 1;
837 		return 0;
838 	}
839 
840 	if (priv->tx_dma_use) {
841 		dev_dbg(priv->port.dev, "%s:Tx is not completed. (%lu)\n",
842 			__func__, jiffies);
843 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
844 		priv->tx_empty = 1;
845 		return 0;
846 	}
847 
848 	fifo_size = max(priv->fifo_size, 1);
849 	tx_empty = 1;
850 	if (pop_tx_x(priv, xmit->buf)) {
851 		pch_uart_hal_write(priv, xmit->buf, 1);
852 		port->icount.tx++;
853 		tx_empty = 0;
854 		fifo_size--;
855 	}
856 
857 	bytes = min((int)CIRC_CNT(xmit->head, xmit->tail,
858 			     UART_XMIT_SIZE), CIRC_CNT_TO_END(xmit->head,
859 			     xmit->tail, UART_XMIT_SIZE));
860 	if (!bytes) {
861 		dev_dbg(priv->port.dev, "%s 0 bytes return\n", __func__);
862 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
863 		uart_write_wakeup(port);
864 		return 0;
865 	}
866 
867 	if (bytes > fifo_size) {
868 		num = bytes / fifo_size + 1;
869 		size = fifo_size;
870 		rem = bytes % fifo_size;
871 	} else {
872 		num = 1;
873 		size = bytes;
874 		rem = bytes;
875 	}
876 
877 	dev_dbg(priv->port.dev, "%s num=%d size=%d rem=%d\n",
878 		__func__, num, size, rem);
879 
880 	priv->tx_dma_use = 1;
881 
882 	priv->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
883 
884 	sg_init_table(priv->sg_tx_p, num); /* Initialize SG table */
885 	sg = priv->sg_tx_p;
886 
887 	for (i = 0; i < num; i++, sg++) {
888 		if (i == (num - 1))
889 			sg_set_page(sg, virt_to_page(xmit->buf),
890 				    rem, fifo_size * i);
891 		else
892 			sg_set_page(sg, virt_to_page(xmit->buf),
893 				    size, fifo_size * i);
894 	}
895 
896 	sg = priv->sg_tx_p;
897 	nent = dma_map_sg(port->dev, sg, num, DMA_TO_DEVICE);
898 	if (!nent) {
899 		dev_err(priv->port.dev, "%s:dma_map_sg Failed\n", __func__);
900 		return 0;
901 	}
902 	priv->nent = nent;
903 
904 	for (i = 0; i < nent; i++, sg++) {
905 		sg->offset = (xmit->tail & (UART_XMIT_SIZE - 1)) +
906 			      fifo_size * i;
907 		sg_dma_address(sg) = (sg_dma_address(sg) &
908 				    ~(UART_XMIT_SIZE - 1)) + sg->offset;
909 		if (i == (nent - 1))
910 			sg_dma_len(sg) = rem;
911 		else
912 			sg_dma_len(sg) = size;
913 	}
914 
915 	desc = priv->chan_tx->device->device_prep_slave_sg(priv->chan_tx,
916 					priv->sg_tx_p, nent, DMA_TO_DEVICE,
917 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
918 	if (!desc) {
919 		dev_err(priv->port.dev, "%s:device_prep_slave_sg Failed\n",
920 			__func__);
921 		return 0;
922 	}
923 	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, nent, DMA_TO_DEVICE);
924 	priv->desc_tx = desc;
925 	desc->callback = pch_dma_tx_complete;
926 	desc->callback_param = priv;
927 
928 	desc->tx_submit(desc);
929 
930 	dma_async_issue_pending(priv->chan_tx);
931 
932 	return PCH_UART_HANDLED_TX_INT;
933 }
934 
935 static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
936 {
937 	u8 fcr = ioread8(priv->membase + UART_FCR);
938 
939 	/* Reset FIFO */
940 	fcr |= UART_FCR_CLEAR_RCVR;
941 	iowrite8(fcr, priv->membase + UART_FCR);
942 
943 	if (lsr & PCH_UART_LSR_ERR)
944 		dev_err(&priv->pdev->dev, "Error data in FIFO\n");
945 
946 	if (lsr & UART_LSR_FE)
947 		dev_err(&priv->pdev->dev, "Framing Error\n");
948 
949 	if (lsr & UART_LSR_PE)
950 		dev_err(&priv->pdev->dev, "Parity Error\n");
951 
952 	if (lsr & UART_LSR_OE)
953 		dev_err(&priv->pdev->dev, "Overrun Error\n");
954 }
955 
956 static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
957 {
958 	struct eg20t_port *priv = dev_id;
959 	unsigned int handled;
960 	u8 lsr;
961 	int ret = 0;
962 	unsigned int iid;
963 	unsigned long flags;
964 
965 	spin_lock_irqsave(&priv->port.lock, flags);
966 	handled = 0;
967 	while ((iid = pch_uart_hal_get_iid(priv)) > 1) {
968 		switch (iid) {
969 		case PCH_UART_IID_RLS:	/* Receiver Line Status */
970 			lsr = pch_uart_hal_get_line_status(priv);
971 			if (lsr & (PCH_UART_LSR_ERR | UART_LSR_FE |
972 						UART_LSR_PE | UART_LSR_OE)) {
973 				pch_uart_err_ir(priv, lsr);
974 				ret = PCH_UART_HANDLED_RX_ERR_INT;
975 			}
976 			break;
977 		case PCH_UART_IID_RDR:	/* Received Data Ready */
978 			if (priv->use_dma) {
979 				pch_uart_hal_disable_interrupt(priv,
980 							PCH_UART_HAL_RX_INT);
981 				ret = dma_handle_rx(priv);
982 				if (!ret)
983 					pch_uart_hal_enable_interrupt(priv,
984 							PCH_UART_HAL_RX_INT);
985 			} else {
986 				ret = handle_rx(priv);
987 			}
988 			break;
989 		case PCH_UART_IID_RDR_TO:	/* Received Data Ready
990 						   (FIFO Timeout) */
991 			ret = handle_rx_to(priv);
992 			break;
993 		case PCH_UART_IID_THRE:	/* Transmitter Holding Register
994 						   Empty */
995 			if (priv->use_dma)
996 				ret = dma_handle_tx(priv);
997 			else
998 				ret = handle_tx(priv);
999 			break;
1000 		case PCH_UART_IID_MS:	/* Modem Status */
1001 			ret = PCH_UART_HANDLED_MS_INT;
1002 			break;
1003 		default:	/* Never junp to this label */
1004 			dev_err(priv->port.dev, "%s:iid=%d (%lu)\n", __func__,
1005 				iid, jiffies);
1006 			ret = -1;
1007 			break;
1008 		}
1009 		handled |= (unsigned int)ret;
1010 	}
1011 	if (handled == 0 && iid <= 1) {
1012 		if (priv->int_dis_flag)
1013 			priv->int_dis_flag = 0;
1014 	}
1015 
1016 	spin_unlock_irqrestore(&priv->port.lock, flags);
1017 	return IRQ_RETVAL(handled);
1018 }
1019 
1020 /* This function tests whether the transmitter fifo and shifter for the port
1021 						described by 'port' is empty. */
1022 static unsigned int pch_uart_tx_empty(struct uart_port *port)
1023 {
1024 	struct eg20t_port *priv;
1025 	int ret;
1026 	priv = container_of(port, struct eg20t_port, port);
1027 	if (priv->tx_empty)
1028 		ret = TIOCSER_TEMT;
1029 	else
1030 		ret = 0;
1031 
1032 	return ret;
1033 }
1034 
1035 /* Returns the current state of modem control inputs. */
1036 static unsigned int pch_uart_get_mctrl(struct uart_port *port)
1037 {
1038 	struct eg20t_port *priv;
1039 	u8 modem;
1040 	unsigned int ret = 0;
1041 
1042 	priv = container_of(port, struct eg20t_port, port);
1043 	modem = pch_uart_hal_get_modem(priv);
1044 
1045 	if (modem & UART_MSR_DCD)
1046 		ret |= TIOCM_CAR;
1047 
1048 	if (modem & UART_MSR_RI)
1049 		ret |= TIOCM_RNG;
1050 
1051 	if (modem & UART_MSR_DSR)
1052 		ret |= TIOCM_DSR;
1053 
1054 	if (modem & UART_MSR_CTS)
1055 		ret |= TIOCM_CTS;
1056 
1057 	return ret;
1058 }
1059 
1060 static void pch_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1061 {
1062 	u32 mcr = 0;
1063 	struct eg20t_port *priv = container_of(port, struct eg20t_port, port);
1064 
1065 	if (mctrl & TIOCM_DTR)
1066 		mcr |= UART_MCR_DTR;
1067 	if (mctrl & TIOCM_RTS)
1068 		mcr |= UART_MCR_RTS;
1069 	if (mctrl & TIOCM_LOOP)
1070 		mcr |= UART_MCR_LOOP;
1071 
1072 	if (priv->mcr & UART_MCR_AFE)
1073 		mcr |= UART_MCR_AFE;
1074 
1075 	if (mctrl)
1076 		iowrite8(mcr, priv->membase + UART_MCR);
1077 }
1078 
1079 static void pch_uart_stop_tx(struct uart_port *port)
1080 {
1081 	struct eg20t_port *priv;
1082 	priv = container_of(port, struct eg20t_port, port);
1083 	priv->start_tx = 0;
1084 	priv->tx_dma_use = 0;
1085 }
1086 
1087 static void pch_uart_start_tx(struct uart_port *port)
1088 {
1089 	struct eg20t_port *priv;
1090 
1091 	priv = container_of(port, struct eg20t_port, port);
1092 
1093 	if (priv->use_dma) {
1094 		if (priv->tx_dma_use) {
1095 			dev_dbg(priv->port.dev, "%s : Tx DMA is NOT empty.\n",
1096 				__func__);
1097 			return;
1098 		}
1099 	}
1100 
1101 	priv->start_tx = 1;
1102 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
1103 }
1104 
1105 static void pch_uart_stop_rx(struct uart_port *port)
1106 {
1107 	struct eg20t_port *priv;
1108 	priv = container_of(port, struct eg20t_port, port);
1109 	priv->start_rx = 0;
1110 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
1111 	priv->int_dis_flag = 1;
1112 }
1113 
1114 /* Enable the modem status interrupts. */
1115 static void pch_uart_enable_ms(struct uart_port *port)
1116 {
1117 	struct eg20t_port *priv;
1118 	priv = container_of(port, struct eg20t_port, port);
1119 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_MS_INT);
1120 }
1121 
1122 /* Control the transmission of a break signal. */
1123 static void pch_uart_break_ctl(struct uart_port *port, int ctl)
1124 {
1125 	struct eg20t_port *priv;
1126 	unsigned long flags;
1127 
1128 	priv = container_of(port, struct eg20t_port, port);
1129 	spin_lock_irqsave(&port->lock, flags);
1130 	pch_uart_hal_set_break(priv, ctl);
1131 	spin_unlock_irqrestore(&port->lock, flags);
1132 }
1133 
1134 /* Grab any interrupt resources and initialise any low level driver state. */
1135 static int pch_uart_startup(struct uart_port *port)
1136 {
1137 	struct eg20t_port *priv;
1138 	int ret;
1139 	int fifo_size;
1140 	int trigger_level;
1141 
1142 	priv = container_of(port, struct eg20t_port, port);
1143 	priv->tx_empty = 1;
1144 
1145 	if (port->uartclk)
1146 		priv->base_baud = port->uartclk;
1147 	else
1148 		port->uartclk = priv->base_baud;
1149 
1150 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1151 	ret = pch_uart_hal_set_line(priv, default_baud,
1152 			      PCH_UART_HAL_PARITY_NONE, PCH_UART_HAL_8BIT,
1153 			      PCH_UART_HAL_STB1);
1154 	if (ret)
1155 		return ret;
1156 
1157 	switch (priv->fifo_size) {
1158 	case 256:
1159 		fifo_size = PCH_UART_HAL_FIFO256;
1160 		break;
1161 	case 64:
1162 		fifo_size = PCH_UART_HAL_FIFO64;
1163 		break;
1164 	case 16:
1165 		fifo_size = PCH_UART_HAL_FIFO16;
1166 	case 1:
1167 	default:
1168 		fifo_size = PCH_UART_HAL_FIFO_DIS;
1169 		break;
1170 	}
1171 
1172 	switch (priv->trigger) {
1173 	case PCH_UART_HAL_TRIGGER1:
1174 		trigger_level = 1;
1175 		break;
1176 	case PCH_UART_HAL_TRIGGER_L:
1177 		trigger_level = priv->fifo_size / 4;
1178 		break;
1179 	case PCH_UART_HAL_TRIGGER_M:
1180 		trigger_level = priv->fifo_size / 2;
1181 		break;
1182 	case PCH_UART_HAL_TRIGGER_H:
1183 	default:
1184 		trigger_level = priv->fifo_size - (priv->fifo_size / 8);
1185 		break;
1186 	}
1187 
1188 	priv->trigger_level = trigger_level;
1189 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1190 				    fifo_size, priv->trigger);
1191 	if (ret < 0)
1192 		return ret;
1193 
1194 	ret = request_irq(priv->port.irq, pch_uart_interrupt, IRQF_SHARED,
1195 			KBUILD_MODNAME, priv);
1196 	if (ret < 0)
1197 		return ret;
1198 
1199 	if (priv->use_dma)
1200 		pch_request_dma(port);
1201 
1202 	priv->start_rx = 1;
1203 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
1204 	uart_update_timeout(port, CS8, default_baud);
1205 
1206 	return 0;
1207 }
1208 
1209 static void pch_uart_shutdown(struct uart_port *port)
1210 {
1211 	struct eg20t_port *priv;
1212 	int ret;
1213 
1214 	priv = container_of(port, struct eg20t_port, port);
1215 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1216 	pch_uart_hal_fifo_reset(priv, PCH_UART_HAL_CLR_ALL_FIFO);
1217 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1218 			      PCH_UART_HAL_FIFO_DIS, PCH_UART_HAL_TRIGGER1);
1219 	if (ret)
1220 		dev_err(priv->port.dev,
1221 			"pch_uart_hal_set_fifo Failed(ret=%d)\n", ret);
1222 
1223 	pch_free_dma(port);
1224 
1225 	free_irq(priv->port.irq, priv);
1226 }
1227 
1228 /* Change the port parameters, including word length, parity, stop
1229  *bits.  Update read_status_mask and ignore_status_mask to indicate
1230  *the types of events we are interested in receiving.  */
1231 static void pch_uart_set_termios(struct uart_port *port,
1232 				 struct ktermios *termios, struct ktermios *old)
1233 {
1234 	int baud;
1235 	int rtn;
1236 	unsigned int parity, bits, stb;
1237 	struct eg20t_port *priv;
1238 	unsigned long flags;
1239 
1240 	priv = container_of(port, struct eg20t_port, port);
1241 	switch (termios->c_cflag & CSIZE) {
1242 	case CS5:
1243 		bits = PCH_UART_HAL_5BIT;
1244 		break;
1245 	case CS6:
1246 		bits = PCH_UART_HAL_6BIT;
1247 		break;
1248 	case CS7:
1249 		bits = PCH_UART_HAL_7BIT;
1250 		break;
1251 	default:		/* CS8 */
1252 		bits = PCH_UART_HAL_8BIT;
1253 		break;
1254 	}
1255 	if (termios->c_cflag & CSTOPB)
1256 		stb = PCH_UART_HAL_STB2;
1257 	else
1258 		stb = PCH_UART_HAL_STB1;
1259 
1260 	if (termios->c_cflag & PARENB) {
1261 		if (!(termios->c_cflag & PARODD))
1262 			parity = PCH_UART_HAL_PARITY_ODD;
1263 		else
1264 			parity = PCH_UART_HAL_PARITY_EVEN;
1265 
1266 	} else {
1267 		parity = PCH_UART_HAL_PARITY_NONE;
1268 	}
1269 
1270 	/* Only UART0 has auto hardware flow function */
1271 	if ((termios->c_cflag & CRTSCTS) && (priv->fifo_size == 256))
1272 		priv->mcr |= UART_MCR_AFE;
1273 	else
1274 		priv->mcr &= ~UART_MCR_AFE;
1275 
1276 	termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
1277 
1278 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
1279 
1280 	spin_lock_irqsave(&port->lock, flags);
1281 
1282 	uart_update_timeout(port, termios->c_cflag, baud);
1283 	rtn = pch_uart_hal_set_line(priv, baud, parity, bits, stb);
1284 	if (rtn)
1285 		goto out;
1286 
1287 	pch_uart_set_mctrl(&priv->port, priv->port.mctrl);
1288 	/* Don't rewrite B0 */
1289 	if (tty_termios_baud_rate(termios))
1290 		tty_termios_encode_baud_rate(termios, baud, baud);
1291 
1292 out:
1293 	spin_unlock_irqrestore(&port->lock, flags);
1294 }
1295 
1296 static const char *pch_uart_type(struct uart_port *port)
1297 {
1298 	return KBUILD_MODNAME;
1299 }
1300 
1301 static void pch_uart_release_port(struct uart_port *port)
1302 {
1303 	struct eg20t_port *priv;
1304 
1305 	priv = container_of(port, struct eg20t_port, port);
1306 	pci_iounmap(priv->pdev, priv->membase);
1307 	pci_release_regions(priv->pdev);
1308 }
1309 
1310 static int pch_uart_request_port(struct uart_port *port)
1311 {
1312 	struct eg20t_port *priv;
1313 	int ret;
1314 	void __iomem *membase;
1315 
1316 	priv = container_of(port, struct eg20t_port, port);
1317 	ret = pci_request_regions(priv->pdev, KBUILD_MODNAME);
1318 	if (ret < 0)
1319 		return -EBUSY;
1320 
1321 	membase = pci_iomap(priv->pdev, 1, 0);
1322 	if (!membase) {
1323 		pci_release_regions(priv->pdev);
1324 		return -EBUSY;
1325 	}
1326 	priv->membase = port->membase = membase;
1327 
1328 	return 0;
1329 }
1330 
1331 static void pch_uart_config_port(struct uart_port *port, int type)
1332 {
1333 	struct eg20t_port *priv;
1334 
1335 	priv = container_of(port, struct eg20t_port, port);
1336 	if (type & UART_CONFIG_TYPE) {
1337 		port->type = priv->port_type;
1338 		pch_uart_request_port(port);
1339 	}
1340 }
1341 
1342 static int pch_uart_verify_port(struct uart_port *port,
1343 				struct serial_struct *serinfo)
1344 {
1345 	struct eg20t_port *priv;
1346 
1347 	priv = container_of(port, struct eg20t_port, port);
1348 	if (serinfo->flags & UPF_LOW_LATENCY) {
1349 		dev_info(priv->port.dev,
1350 			"PCH UART : Use PIO Mode (without DMA)\n");
1351 		priv->use_dma = 0;
1352 		serinfo->flags &= ~UPF_LOW_LATENCY;
1353 	} else {
1354 #ifndef CONFIG_PCH_DMA
1355 		dev_err(priv->port.dev, "%s : PCH DMA is not Loaded.\n",
1356 			__func__);
1357 		return -EOPNOTSUPP;
1358 #endif
1359 		priv->use_dma = 1;
1360 		priv->use_dma_flag = 1;
1361 		dev_info(priv->port.dev, "PCH UART : Use DMA Mode\n");
1362 	}
1363 
1364 	return 0;
1365 }
1366 
1367 static struct uart_ops pch_uart_ops = {
1368 	.tx_empty = pch_uart_tx_empty,
1369 	.set_mctrl = pch_uart_set_mctrl,
1370 	.get_mctrl = pch_uart_get_mctrl,
1371 	.stop_tx = pch_uart_stop_tx,
1372 	.start_tx = pch_uart_start_tx,
1373 	.stop_rx = pch_uart_stop_rx,
1374 	.enable_ms = pch_uart_enable_ms,
1375 	.break_ctl = pch_uart_break_ctl,
1376 	.startup = pch_uart_startup,
1377 	.shutdown = pch_uart_shutdown,
1378 	.set_termios = pch_uart_set_termios,
1379 /*	.pm		= pch_uart_pm,		Not supported yet */
1380 /*	.set_wake	= pch_uart_set_wake,	Not supported yet */
1381 	.type = pch_uart_type,
1382 	.release_port = pch_uart_release_port,
1383 	.request_port = pch_uart_request_port,
1384 	.config_port = pch_uart_config_port,
1385 	.verify_port = pch_uart_verify_port
1386 };
1387 
1388 static struct uart_driver pch_uart_driver = {
1389 	.owner = THIS_MODULE,
1390 	.driver_name = KBUILD_MODNAME,
1391 	.dev_name = PCH_UART_DRIVER_DEVICE,
1392 	.major = 0,
1393 	.minor = 0,
1394 	.nr = PCH_UART_NR,
1395 };
1396 
1397 static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
1398 					     const struct pci_device_id *id)
1399 {
1400 	struct eg20t_port *priv;
1401 	int ret;
1402 	unsigned int iobase;
1403 	unsigned int mapbase;
1404 	unsigned char *rxbuf;
1405 	int fifosize, base_baud;
1406 	int port_type;
1407 	struct pch_uart_driver_data *board;
1408 	const char *board_name;
1409 
1410 	board = &drv_dat[id->driver_data];
1411 	port_type = board->port_type;
1412 
1413 	priv = kzalloc(sizeof(struct eg20t_port), GFP_KERNEL);
1414 	if (priv == NULL)
1415 		goto init_port_alloc_err;
1416 
1417 	rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
1418 	if (!rxbuf)
1419 		goto init_port_free_txbuf;
1420 
1421 	base_baud = 1843200; /* 1.8432MHz */
1422 
1423 	/* quirk for CM-iTC board */
1424 	board_name = dmi_get_system_info(DMI_BOARD_NAME);
1425 	if (board_name && strstr(board_name, "CM-iTC"))
1426 		base_baud = 192000000; /* 192.0MHz */
1427 
1428 	switch (port_type) {
1429 	case PORT_UNKNOWN:
1430 		fifosize = 256; /* EG20T/ML7213: UART0 */
1431 		break;
1432 	case PORT_8250:
1433 		fifosize = 64; /* EG20T:UART1~3  ML7213: UART1~2*/
1434 		break;
1435 	default:
1436 		dev_err(&pdev->dev, "Invalid Port Type(=%d)\n", port_type);
1437 		goto init_port_hal_free;
1438 	}
1439 
1440 	pci_enable_msi(pdev);
1441 
1442 	iobase = pci_resource_start(pdev, 0);
1443 	mapbase = pci_resource_start(pdev, 1);
1444 	priv->mapbase = mapbase;
1445 	priv->iobase = iobase;
1446 	priv->pdev = pdev;
1447 	priv->tx_empty = 1;
1448 	priv->rxbuf.buf = rxbuf;
1449 	priv->rxbuf.size = PAGE_SIZE;
1450 
1451 	priv->fifo_size = fifosize;
1452 	priv->base_baud = base_baud;
1453 	priv->port_type = PORT_MAX_8250 + port_type + 1;
1454 	priv->port.dev = &pdev->dev;
1455 	priv->port.iobase = iobase;
1456 	priv->port.membase = NULL;
1457 	priv->port.mapbase = mapbase;
1458 	priv->port.irq = pdev->irq;
1459 	priv->port.iotype = UPIO_PORT;
1460 	priv->port.ops = &pch_uart_ops;
1461 	priv->port.flags = UPF_BOOT_AUTOCONF;
1462 	priv->port.fifosize = fifosize;
1463 	priv->port.line = board->line_no;
1464 	priv->trigger = PCH_UART_HAL_TRIGGER_M;
1465 
1466 	spin_lock_init(&priv->port.lock);
1467 
1468 	pci_set_drvdata(pdev, priv);
1469 	pch_uart_hal_request(pdev, fifosize, base_baud);
1470 
1471 	ret = uart_add_one_port(&pch_uart_driver, &priv->port);
1472 	if (ret < 0)
1473 		goto init_port_hal_free;
1474 
1475 	return priv;
1476 
1477 init_port_hal_free:
1478 	free_page((unsigned long)rxbuf);
1479 init_port_free_txbuf:
1480 	kfree(priv);
1481 init_port_alloc_err:
1482 
1483 	return NULL;
1484 }
1485 
1486 static void pch_uart_exit_port(struct eg20t_port *priv)
1487 {
1488 	uart_remove_one_port(&pch_uart_driver, &priv->port);
1489 	pci_set_drvdata(priv->pdev, NULL);
1490 	free_page((unsigned long)priv->rxbuf.buf);
1491 }
1492 
1493 static void pch_uart_pci_remove(struct pci_dev *pdev)
1494 {
1495 	struct eg20t_port *priv;
1496 
1497 	priv = (struct eg20t_port *)pci_get_drvdata(pdev);
1498 
1499 	pci_disable_msi(pdev);
1500 	pch_uart_exit_port(priv);
1501 	pci_disable_device(pdev);
1502 	kfree(priv);
1503 	return;
1504 }
1505 #ifdef CONFIG_PM
1506 static int pch_uart_pci_suspend(struct pci_dev *pdev, pm_message_t state)
1507 {
1508 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1509 
1510 	uart_suspend_port(&pch_uart_driver, &priv->port);
1511 
1512 	pci_save_state(pdev);
1513 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1514 	return 0;
1515 }
1516 
1517 static int pch_uart_pci_resume(struct pci_dev *pdev)
1518 {
1519 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1520 	int ret;
1521 
1522 	pci_set_power_state(pdev, PCI_D0);
1523 	pci_restore_state(pdev);
1524 
1525 	ret = pci_enable_device(pdev);
1526 	if (ret) {
1527 		dev_err(&pdev->dev,
1528 		"%s-pci_enable_device failed(ret=%d) ", __func__, ret);
1529 		return ret;
1530 	}
1531 
1532 	uart_resume_port(&pch_uart_driver, &priv->port);
1533 
1534 	return 0;
1535 }
1536 #else
1537 #define pch_uart_pci_suspend NULL
1538 #define pch_uart_pci_resume NULL
1539 #endif
1540 
1541 static DEFINE_PCI_DEVICE_TABLE(pch_uart_pci_id) = {
1542 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8811),
1543 	 .driver_data = pch_et20t_uart0},
1544 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8812),
1545 	 .driver_data = pch_et20t_uart1},
1546 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8813),
1547 	 .driver_data = pch_et20t_uart2},
1548 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8814),
1549 	 .driver_data = pch_et20t_uart3},
1550 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8027),
1551 	 .driver_data = pch_ml7213_uart0},
1552 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8028),
1553 	 .driver_data = pch_ml7213_uart1},
1554 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8029),
1555 	 .driver_data = pch_ml7213_uart2},
1556 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800C),
1557 	 .driver_data = pch_ml7223_uart0},
1558 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800D),
1559 	 .driver_data = pch_ml7223_uart1},
1560 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8811),
1561 	 .driver_data = pch_ml7831_uart0},
1562 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8812),
1563 	 .driver_data = pch_ml7831_uart1},
1564 	{0,},
1565 };
1566 
1567 static int __devinit pch_uart_pci_probe(struct pci_dev *pdev,
1568 					const struct pci_device_id *id)
1569 {
1570 	int ret;
1571 	struct eg20t_port *priv;
1572 
1573 	ret = pci_enable_device(pdev);
1574 	if (ret < 0)
1575 		goto probe_error;
1576 
1577 	priv = pch_uart_init_port(pdev, id);
1578 	if (!priv) {
1579 		ret = -EBUSY;
1580 		goto probe_disable_device;
1581 	}
1582 	pci_set_drvdata(pdev, priv);
1583 
1584 	return ret;
1585 
1586 probe_disable_device:
1587 	pci_disable_msi(pdev);
1588 	pci_disable_device(pdev);
1589 probe_error:
1590 	return ret;
1591 }
1592 
1593 static struct pci_driver pch_uart_pci_driver = {
1594 	.name = "pch_uart",
1595 	.id_table = pch_uart_pci_id,
1596 	.probe = pch_uart_pci_probe,
1597 	.remove = __devexit_p(pch_uart_pci_remove),
1598 	.suspend = pch_uart_pci_suspend,
1599 	.resume = pch_uart_pci_resume,
1600 };
1601 
1602 static int __init pch_uart_module_init(void)
1603 {
1604 	int ret;
1605 
1606 	/* register as UART driver */
1607 	ret = uart_register_driver(&pch_uart_driver);
1608 	if (ret < 0)
1609 		return ret;
1610 
1611 	/* register as PCI driver */
1612 	ret = pci_register_driver(&pch_uart_pci_driver);
1613 	if (ret < 0)
1614 		uart_unregister_driver(&pch_uart_driver);
1615 
1616 	return ret;
1617 }
1618 module_init(pch_uart_module_init);
1619 
1620 static void __exit pch_uart_module_exit(void)
1621 {
1622 	pci_unregister_driver(&pch_uart_pci_driver);
1623 	uart_unregister_driver(&pch_uart_driver);
1624 }
1625 module_exit(pch_uart_module_exit);
1626 
1627 MODULE_LICENSE("GPL v2");
1628 MODULE_DESCRIPTION("Intel EG20T PCH UART PCI Driver");
1629 module_param(default_baud, uint, S_IRUGO);
1630