xref: /linux/drivers/tty/serial/pch_uart.c (revision c54ea4918c2b7722d7242ea53271356501988a9b)
1 /*
2  *Copyright (C) 2010 OKI 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/serial_reg.h>
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/serial_core.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/dmi.h>
24 
25 #include <linux/dmaengine.h>
26 #include <linux/pch_dma.h>
27 
28 enum {
29 	PCH_UART_HANDLED_RX_INT_SHIFT,
30 	PCH_UART_HANDLED_TX_INT_SHIFT,
31 	PCH_UART_HANDLED_RX_ERR_INT_SHIFT,
32 	PCH_UART_HANDLED_RX_TRG_INT_SHIFT,
33 	PCH_UART_HANDLED_MS_INT_SHIFT,
34 };
35 
36 enum {
37 	PCH_UART_8LINE,
38 	PCH_UART_2LINE,
39 };
40 
41 #define PCH_UART_DRIVER_DEVICE "ttyPCH"
42 
43 /* Set the max number of UART port
44  * Intel EG20T PCH: 4 port
45  * OKI SEMICONDUCTOR ML7213 IOH: 3 port
46 */
47 #define PCH_UART_NR	4
48 
49 #define PCH_UART_HANDLED_RX_INT	(1<<((PCH_UART_HANDLED_RX_INT_SHIFT)<<1))
50 #define PCH_UART_HANDLED_TX_INT	(1<<((PCH_UART_HANDLED_TX_INT_SHIFT)<<1))
51 #define PCH_UART_HANDLED_RX_ERR_INT	(1<<((\
52 					PCH_UART_HANDLED_RX_ERR_INT_SHIFT)<<1))
53 #define PCH_UART_HANDLED_RX_TRG_INT	(1<<((\
54 					PCH_UART_HANDLED_RX_TRG_INT_SHIFT)<<1))
55 #define PCH_UART_HANDLED_MS_INT	(1<<((PCH_UART_HANDLED_MS_INT_SHIFT)<<1))
56 
57 #define PCH_UART_RBR		0x00
58 #define PCH_UART_THR		0x00
59 
60 #define PCH_UART_IER_MASK	(PCH_UART_IER_ERBFI|PCH_UART_IER_ETBEI|\
61 				PCH_UART_IER_ELSI|PCH_UART_IER_EDSSI)
62 #define PCH_UART_IER_ERBFI	0x00000001
63 #define PCH_UART_IER_ETBEI	0x00000002
64 #define PCH_UART_IER_ELSI	0x00000004
65 #define PCH_UART_IER_EDSSI	0x00000008
66 
67 #define PCH_UART_IIR_IP			0x00000001
68 #define PCH_UART_IIR_IID		0x00000006
69 #define PCH_UART_IIR_MSI		0x00000000
70 #define PCH_UART_IIR_TRI		0x00000002
71 #define PCH_UART_IIR_RRI		0x00000004
72 #define PCH_UART_IIR_REI		0x00000006
73 #define PCH_UART_IIR_TOI		0x00000008
74 #define PCH_UART_IIR_FIFO256		0x00000020
75 #define PCH_UART_IIR_FIFO64		PCH_UART_IIR_FIFO256
76 #define PCH_UART_IIR_FE			0x000000C0
77 
78 #define PCH_UART_FCR_FIFOE		0x00000001
79 #define PCH_UART_FCR_RFR		0x00000002
80 #define PCH_UART_FCR_TFR		0x00000004
81 #define PCH_UART_FCR_DMS		0x00000008
82 #define PCH_UART_FCR_FIFO256		0x00000020
83 #define PCH_UART_FCR_RFTL		0x000000C0
84 
85 #define PCH_UART_FCR_RFTL1		0x00000000
86 #define PCH_UART_FCR_RFTL64		0x00000040
87 #define PCH_UART_FCR_RFTL128		0x00000080
88 #define PCH_UART_FCR_RFTL224		0x000000C0
89 #define PCH_UART_FCR_RFTL16		PCH_UART_FCR_RFTL64
90 #define PCH_UART_FCR_RFTL32		PCH_UART_FCR_RFTL128
91 #define PCH_UART_FCR_RFTL56		PCH_UART_FCR_RFTL224
92 #define PCH_UART_FCR_RFTL4		PCH_UART_FCR_RFTL64
93 #define PCH_UART_FCR_RFTL8		PCH_UART_FCR_RFTL128
94 #define PCH_UART_FCR_RFTL14		PCH_UART_FCR_RFTL224
95 #define PCH_UART_FCR_RFTL_SHIFT		6
96 
97 #define PCH_UART_LCR_WLS	0x00000003
98 #define PCH_UART_LCR_STB	0x00000004
99 #define PCH_UART_LCR_PEN	0x00000008
100 #define PCH_UART_LCR_EPS	0x00000010
101 #define PCH_UART_LCR_SP		0x00000020
102 #define PCH_UART_LCR_SB		0x00000040
103 #define PCH_UART_LCR_DLAB	0x00000080
104 #define PCH_UART_LCR_NP		0x00000000
105 #define PCH_UART_LCR_OP		PCH_UART_LCR_PEN
106 #define PCH_UART_LCR_EP		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS)
107 #define PCH_UART_LCR_1P		(PCH_UART_LCR_PEN | PCH_UART_LCR_SP)
108 #define PCH_UART_LCR_0P		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS |\
109 				PCH_UART_LCR_SP)
110 
111 #define PCH_UART_LCR_5BIT	0x00000000
112 #define PCH_UART_LCR_6BIT	0x00000001
113 #define PCH_UART_LCR_7BIT	0x00000002
114 #define PCH_UART_LCR_8BIT	0x00000003
115 
116 #define PCH_UART_MCR_DTR	0x00000001
117 #define PCH_UART_MCR_RTS	0x00000002
118 #define PCH_UART_MCR_OUT	0x0000000C
119 #define PCH_UART_MCR_LOOP	0x00000010
120 #define PCH_UART_MCR_AFE	0x00000020
121 
122 #define PCH_UART_LSR_DR		0x00000001
123 #define PCH_UART_LSR_ERR	(1<<7)
124 
125 #define PCH_UART_MSR_DCTS	0x00000001
126 #define PCH_UART_MSR_DDSR	0x00000002
127 #define PCH_UART_MSR_TERI	0x00000004
128 #define PCH_UART_MSR_DDCD	0x00000008
129 #define PCH_UART_MSR_CTS	0x00000010
130 #define PCH_UART_MSR_DSR	0x00000020
131 #define PCH_UART_MSR_RI		0x00000040
132 #define PCH_UART_MSR_DCD	0x00000080
133 #define PCH_UART_MSR_DELTA	(PCH_UART_MSR_DCTS | PCH_UART_MSR_DDSR |\
134 				PCH_UART_MSR_TERI | PCH_UART_MSR_DDCD)
135 
136 #define PCH_UART_DLL		0x00
137 #define PCH_UART_DLM		0x01
138 
139 #define DIV_ROUND(a, b)	(((a) + ((b)/2)) / (b))
140 
141 #define PCH_UART_IID_RLS	(PCH_UART_IIR_REI)
142 #define PCH_UART_IID_RDR	(PCH_UART_IIR_RRI)
143 #define PCH_UART_IID_RDR_TO	(PCH_UART_IIR_RRI | PCH_UART_IIR_TOI)
144 #define PCH_UART_IID_THRE	(PCH_UART_IIR_TRI)
145 #define PCH_UART_IID_MS		(PCH_UART_IIR_MSI)
146 
147 #define PCH_UART_HAL_PARITY_NONE	(PCH_UART_LCR_NP)
148 #define PCH_UART_HAL_PARITY_ODD		(PCH_UART_LCR_OP)
149 #define PCH_UART_HAL_PARITY_EVEN	(PCH_UART_LCR_EP)
150 #define PCH_UART_HAL_PARITY_FIX1	(PCH_UART_LCR_1P)
151 #define PCH_UART_HAL_PARITY_FIX0	(PCH_UART_LCR_0P)
152 #define PCH_UART_HAL_5BIT		(PCH_UART_LCR_5BIT)
153 #define PCH_UART_HAL_6BIT		(PCH_UART_LCR_6BIT)
154 #define PCH_UART_HAL_7BIT		(PCH_UART_LCR_7BIT)
155 #define PCH_UART_HAL_8BIT		(PCH_UART_LCR_8BIT)
156 #define PCH_UART_HAL_STB1		0
157 #define PCH_UART_HAL_STB2		(PCH_UART_LCR_STB)
158 
159 #define PCH_UART_HAL_CLR_TX_FIFO	(PCH_UART_FCR_TFR)
160 #define PCH_UART_HAL_CLR_RX_FIFO	(PCH_UART_FCR_RFR)
161 #define PCH_UART_HAL_CLR_ALL_FIFO	(PCH_UART_HAL_CLR_TX_FIFO | \
162 					PCH_UART_HAL_CLR_RX_FIFO)
163 
164 #define PCH_UART_HAL_DMA_MODE0		0
165 #define PCH_UART_HAL_FIFO_DIS		0
166 #define PCH_UART_HAL_FIFO16		(PCH_UART_FCR_FIFOE)
167 #define PCH_UART_HAL_FIFO256		(PCH_UART_FCR_FIFOE | \
168 					PCH_UART_FCR_FIFO256)
169 #define PCH_UART_HAL_FIFO64		(PCH_UART_HAL_FIFO256)
170 #define PCH_UART_HAL_TRIGGER1		(PCH_UART_FCR_RFTL1)
171 #define PCH_UART_HAL_TRIGGER64		(PCH_UART_FCR_RFTL64)
172 #define PCH_UART_HAL_TRIGGER128		(PCH_UART_FCR_RFTL128)
173 #define PCH_UART_HAL_TRIGGER224		(PCH_UART_FCR_RFTL224)
174 #define PCH_UART_HAL_TRIGGER16		(PCH_UART_FCR_RFTL16)
175 #define PCH_UART_HAL_TRIGGER32		(PCH_UART_FCR_RFTL32)
176 #define PCH_UART_HAL_TRIGGER56		(PCH_UART_FCR_RFTL56)
177 #define PCH_UART_HAL_TRIGGER4		(PCH_UART_FCR_RFTL4)
178 #define PCH_UART_HAL_TRIGGER8		(PCH_UART_FCR_RFTL8)
179 #define PCH_UART_HAL_TRIGGER14		(PCH_UART_FCR_RFTL14)
180 #define PCH_UART_HAL_TRIGGER_L		(PCH_UART_FCR_RFTL64)
181 #define PCH_UART_HAL_TRIGGER_M		(PCH_UART_FCR_RFTL128)
182 #define PCH_UART_HAL_TRIGGER_H		(PCH_UART_FCR_RFTL224)
183 
184 #define PCH_UART_HAL_RX_INT		(PCH_UART_IER_ERBFI)
185 #define PCH_UART_HAL_TX_INT		(PCH_UART_IER_ETBEI)
186 #define PCH_UART_HAL_RX_ERR_INT		(PCH_UART_IER_ELSI)
187 #define PCH_UART_HAL_MS_INT		(PCH_UART_IER_EDSSI)
188 #define PCH_UART_HAL_ALL_INT		(PCH_UART_IER_MASK)
189 
190 #define PCH_UART_HAL_DTR		(PCH_UART_MCR_DTR)
191 #define PCH_UART_HAL_RTS		(PCH_UART_MCR_RTS)
192 #define PCH_UART_HAL_OUT		(PCH_UART_MCR_OUT)
193 #define PCH_UART_HAL_LOOP		(PCH_UART_MCR_LOOP)
194 #define PCH_UART_HAL_AFE		(PCH_UART_MCR_AFE)
195 
196 #define PCI_VENDOR_ID_ROHM		0x10DB
197 
198 struct pch_uart_buffer {
199 	unsigned char *buf;
200 	int size;
201 };
202 
203 struct eg20t_port {
204 	struct uart_port port;
205 	int port_type;
206 	void __iomem *membase;
207 	resource_size_t mapbase;
208 	unsigned int iobase;
209 	struct pci_dev *pdev;
210 	int fifo_size;
211 	int base_baud;
212 	int start_tx;
213 	int start_rx;
214 	int tx_empty;
215 	int int_dis_flag;
216 	int trigger;
217 	int trigger_level;
218 	struct pch_uart_buffer rxbuf;
219 	unsigned int dmsr;
220 	unsigned int fcr;
221 	unsigned int mcr;
222 	unsigned int use_dma;
223 	unsigned int use_dma_flag;
224 	struct dma_async_tx_descriptor	*desc_tx;
225 	struct dma_async_tx_descriptor	*desc_rx;
226 	struct pch_dma_slave		param_tx;
227 	struct pch_dma_slave		param_rx;
228 	struct dma_chan			*chan_tx;
229 	struct dma_chan			*chan_rx;
230 	struct scatterlist		*sg_tx_p;
231 	int				nent;
232 	struct scatterlist		sg_rx;
233 	int				tx_dma_use;
234 	void				*rx_buf_virt;
235 	dma_addr_t			rx_buf_dma;
236 };
237 
238 /**
239  * struct pch_uart_driver_data - private data structure for UART-DMA
240  * @port_type:			The number of DMA channel
241  * @line_no:			UART port line number (0, 1, 2...)
242  */
243 struct pch_uart_driver_data {
244 	int port_type;
245 	int line_no;
246 };
247 
248 enum pch_uart_num_t {
249 	pch_et20t_uart0 = 0,
250 	pch_et20t_uart1,
251 	pch_et20t_uart2,
252 	pch_et20t_uart3,
253 	pch_ml7213_uart0,
254 	pch_ml7213_uart1,
255 	pch_ml7213_uart2,
256 };
257 
258 static struct pch_uart_driver_data drv_dat[] = {
259 	[pch_et20t_uart0] = {PCH_UART_8LINE, 0},
260 	[pch_et20t_uart1] = {PCH_UART_2LINE, 1},
261 	[pch_et20t_uart2] = {PCH_UART_2LINE, 2},
262 	[pch_et20t_uart3] = {PCH_UART_2LINE, 3},
263 	[pch_ml7213_uart0] = {PCH_UART_8LINE, 0},
264 	[pch_ml7213_uart1] = {PCH_UART_2LINE, 1},
265 	[pch_ml7213_uart2] = {PCH_UART_2LINE, 2},
266 };
267 
268 static unsigned int default_baud = 9600;
269 static const int trigger_level_256[4] = { 1, 64, 128, 224 };
270 static const int trigger_level_64[4] = { 1, 16, 32, 56 };
271 static const int trigger_level_16[4] = { 1, 4, 8, 14 };
272 static const int trigger_level_1[4] = { 1, 1, 1, 1 };
273 
274 static void pch_uart_hal_request(struct pci_dev *pdev, int fifosize,
275 				 int base_baud)
276 {
277 	struct eg20t_port *priv = pci_get_drvdata(pdev);
278 
279 	priv->trigger_level = 1;
280 	priv->fcr = 0;
281 }
282 
283 static unsigned int get_msr(struct eg20t_port *priv, void __iomem *base)
284 {
285 	unsigned int msr = ioread8(base + UART_MSR);
286 	priv->dmsr |= msr & PCH_UART_MSR_DELTA;
287 
288 	return msr;
289 }
290 
291 static void pch_uart_hal_enable_interrupt(struct eg20t_port *priv,
292 					  unsigned int flag)
293 {
294 	u8 ier = ioread8(priv->membase + UART_IER);
295 	ier |= flag & PCH_UART_IER_MASK;
296 	iowrite8(ier, priv->membase + UART_IER);
297 }
298 
299 static void pch_uart_hal_disable_interrupt(struct eg20t_port *priv,
300 					   unsigned int flag)
301 {
302 	u8 ier = ioread8(priv->membase + UART_IER);
303 	ier &= ~(flag & PCH_UART_IER_MASK);
304 	iowrite8(ier, priv->membase + UART_IER);
305 }
306 
307 static int pch_uart_hal_set_line(struct eg20t_port *priv, int baud,
308 				 unsigned int parity, unsigned int bits,
309 				 unsigned int stb)
310 {
311 	unsigned int dll, dlm, lcr;
312 	int div;
313 
314 	div = DIV_ROUND(priv->base_baud / 16, baud);
315 	if (div < 0 || USHRT_MAX <= div) {
316 		dev_err(priv->port.dev, "Invalid Baud(div=0x%x)\n", div);
317 		return -EINVAL;
318 	}
319 
320 	dll = (unsigned int)div & 0x00FFU;
321 	dlm = ((unsigned int)div >> 8) & 0x00FFU;
322 
323 	if (parity & ~(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS | PCH_UART_LCR_SP)) {
324 		dev_err(priv->port.dev, "Invalid parity(0x%x)\n", parity);
325 		return -EINVAL;
326 	}
327 
328 	if (bits & ~PCH_UART_LCR_WLS) {
329 		dev_err(priv->port.dev, "Invalid bits(0x%x)\n", bits);
330 		return -EINVAL;
331 	}
332 
333 	if (stb & ~PCH_UART_LCR_STB) {
334 		dev_err(priv->port.dev, "Invalid STB(0x%x)\n", stb);
335 		return -EINVAL;
336 	}
337 
338 	lcr = parity;
339 	lcr |= bits;
340 	lcr |= stb;
341 
342 	dev_dbg(priv->port.dev, "%s:baud = %d, div = %04x, lcr = %02x (%lu)\n",
343 		 __func__, baud, div, lcr, jiffies);
344 	iowrite8(PCH_UART_LCR_DLAB, priv->membase + UART_LCR);
345 	iowrite8(dll, priv->membase + PCH_UART_DLL);
346 	iowrite8(dlm, priv->membase + PCH_UART_DLM);
347 	iowrite8(lcr, priv->membase + UART_LCR);
348 
349 	return 0;
350 }
351 
352 static int pch_uart_hal_fifo_reset(struct eg20t_port *priv,
353 				    unsigned int flag)
354 {
355 	if (flag & ~(PCH_UART_FCR_TFR | PCH_UART_FCR_RFR)) {
356 		dev_err(priv->port.dev, "%s:Invalid flag(0x%x)\n",
357 			__func__, flag);
358 		return -EINVAL;
359 	}
360 
361 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr, priv->membase + UART_FCR);
362 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr | flag,
363 		 priv->membase + UART_FCR);
364 	iowrite8(priv->fcr, priv->membase + UART_FCR);
365 
366 	return 0;
367 }
368 
369 static int pch_uart_hal_set_fifo(struct eg20t_port *priv,
370 				 unsigned int dmamode,
371 				 unsigned int fifo_size, unsigned int trigger)
372 {
373 	u8 fcr;
374 
375 	if (dmamode & ~PCH_UART_FCR_DMS) {
376 		dev_err(priv->port.dev, "%s:Invalid DMA Mode(0x%x)\n",
377 			__func__, dmamode);
378 		return -EINVAL;
379 	}
380 
381 	if (fifo_size & ~(PCH_UART_FCR_FIFOE | PCH_UART_FCR_FIFO256)) {
382 		dev_err(priv->port.dev, "%s:Invalid FIFO SIZE(0x%x)\n",
383 			__func__, fifo_size);
384 		return -EINVAL;
385 	}
386 
387 	if (trigger & ~PCH_UART_FCR_RFTL) {
388 		dev_err(priv->port.dev, "%s:Invalid TRIGGER(0x%x)\n",
389 			__func__, trigger);
390 		return -EINVAL;
391 	}
392 
393 	switch (priv->fifo_size) {
394 	case 256:
395 		priv->trigger_level =
396 		    trigger_level_256[trigger >> PCH_UART_FCR_RFTL_SHIFT];
397 		break;
398 	case 64:
399 		priv->trigger_level =
400 		    trigger_level_64[trigger >> PCH_UART_FCR_RFTL_SHIFT];
401 		break;
402 	case 16:
403 		priv->trigger_level =
404 		    trigger_level_16[trigger >> PCH_UART_FCR_RFTL_SHIFT];
405 		break;
406 	default:
407 		priv->trigger_level =
408 		    trigger_level_1[trigger >> PCH_UART_FCR_RFTL_SHIFT];
409 		break;
410 	}
411 	fcr =
412 	    dmamode | fifo_size | trigger | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR;
413 	iowrite8(PCH_UART_FCR_FIFOE, priv->membase + UART_FCR);
414 	iowrite8(PCH_UART_FCR_FIFOE | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR,
415 		 priv->membase + UART_FCR);
416 	iowrite8(fcr, priv->membase + UART_FCR);
417 	priv->fcr = fcr;
418 
419 	return 0;
420 }
421 
422 static u8 pch_uart_hal_get_modem(struct eg20t_port *priv)
423 {
424 	priv->dmsr = 0;
425 	return get_msr(priv, priv->membase);
426 }
427 
428 static void pch_uart_hal_write(struct eg20t_port *priv,
429 			      const unsigned char *buf, int tx_size)
430 {
431 	int i;
432 	unsigned int thr;
433 
434 	for (i = 0; i < tx_size;) {
435 		thr = buf[i++];
436 		iowrite8(thr, priv->membase + PCH_UART_THR);
437 	}
438 }
439 
440 static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
441 			     int rx_size)
442 {
443 	int i;
444 	u8 rbr, lsr;
445 
446 	lsr = ioread8(priv->membase + UART_LSR);
447 	for (i = 0, lsr = ioread8(priv->membase + UART_LSR);
448 	     i < rx_size && lsr & UART_LSR_DR;
449 	     lsr = ioread8(priv->membase + UART_LSR)) {
450 		rbr = ioread8(priv->membase + PCH_UART_RBR);
451 		buf[i++] = rbr;
452 	}
453 	return i;
454 }
455 
456 static unsigned int pch_uart_hal_get_iid(struct eg20t_port *priv)
457 {
458 	unsigned int iir;
459 	int ret;
460 
461 	iir = ioread8(priv->membase + UART_IIR);
462 	ret = (iir & (PCH_UART_IIR_IID | PCH_UART_IIR_TOI | PCH_UART_IIR_IP));
463 	return ret;
464 }
465 
466 static u8 pch_uart_hal_get_line_status(struct eg20t_port *priv)
467 {
468 	return ioread8(priv->membase + UART_LSR);
469 }
470 
471 static void pch_uart_hal_set_break(struct eg20t_port *priv, int on)
472 {
473 	unsigned int lcr;
474 
475 	lcr = ioread8(priv->membase + UART_LCR);
476 	if (on)
477 		lcr |= PCH_UART_LCR_SB;
478 	else
479 		lcr &= ~PCH_UART_LCR_SB;
480 
481 	iowrite8(lcr, priv->membase + UART_LCR);
482 }
483 
484 static int push_rx(struct eg20t_port *priv, const unsigned char *buf,
485 		   int size)
486 {
487 	struct uart_port *port;
488 	struct tty_struct *tty;
489 
490 	port = &priv->port;
491 	tty = tty_port_tty_get(&port->state->port);
492 	if (!tty) {
493 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
494 		return -EBUSY;
495 	}
496 
497 	tty_insert_flip_string(tty, buf, size);
498 	tty_flip_buffer_push(tty);
499 	tty_kref_put(tty);
500 
501 	return 0;
502 }
503 
504 static int pop_tx_x(struct eg20t_port *priv, unsigned char *buf)
505 {
506 	int ret;
507 	struct uart_port *port = &priv->port;
508 
509 	if (port->x_char) {
510 		dev_dbg(priv->port.dev, "%s:X character send %02x (%lu)\n",
511 			__func__, port->x_char, jiffies);
512 		buf[0] = port->x_char;
513 		port->x_char = 0;
514 		ret = 1;
515 	} else {
516 		ret = 0;
517 	}
518 
519 	return ret;
520 }
521 
522 static int dma_push_rx(struct eg20t_port *priv, int size)
523 {
524 	struct tty_struct *tty;
525 	int room;
526 	struct uart_port *port = &priv->port;
527 
528 	port = &priv->port;
529 	tty = tty_port_tty_get(&port->state->port);
530 	if (!tty) {
531 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
532 		return 0;
533 	}
534 
535 	room = tty_buffer_request_room(tty, size);
536 
537 	if (room < size)
538 		dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
539 			 size - room);
540 	if (!room)
541 		return room;
542 
543 	tty_insert_flip_string(tty, sg_virt(&priv->sg_rx), size);
544 
545 	port->icount.rx += room;
546 	tty_kref_put(tty);
547 
548 	return room;
549 }
550 
551 static void pch_free_dma(struct uart_port *port)
552 {
553 	struct eg20t_port *priv;
554 	priv = container_of(port, struct eg20t_port, port);
555 
556 	if (priv->chan_tx) {
557 		dma_release_channel(priv->chan_tx);
558 		priv->chan_tx = NULL;
559 	}
560 	if (priv->chan_rx) {
561 		dma_release_channel(priv->chan_rx);
562 		priv->chan_rx = NULL;
563 	}
564 	if (sg_dma_address(&priv->sg_rx))
565 		dma_free_coherent(port->dev, port->fifosize,
566 				  sg_virt(&priv->sg_rx),
567 				  sg_dma_address(&priv->sg_rx));
568 
569 	return;
570 }
571 
572 static bool filter(struct dma_chan *chan, void *slave)
573 {
574 	struct pch_dma_slave *param = slave;
575 
576 	if ((chan->chan_id == param->chan_id) && (param->dma_dev ==
577 						  chan->device->dev)) {
578 		chan->private = param;
579 		return true;
580 	} else {
581 		return false;
582 	}
583 }
584 
585 static void pch_request_dma(struct uart_port *port)
586 {
587 	dma_cap_mask_t mask;
588 	struct dma_chan *chan;
589 	struct pci_dev *dma_dev;
590 	struct pch_dma_slave *param;
591 	struct eg20t_port *priv =
592 				container_of(port, struct eg20t_port, port);
593 	dma_cap_zero(mask);
594 	dma_cap_set(DMA_SLAVE, mask);
595 
596 	dma_dev = pci_get_bus_and_slot(2, PCI_DEVFN(0xa, 0)); /* Get DMA's dev
597 								information */
598 	/* Set Tx DMA */
599 	param = &priv->param_tx;
600 	param->dma_dev = &dma_dev->dev;
601 	param->chan_id = priv->port.line * 2; /* Tx = 0, 2, 4, ... */
602 
603 	param->tx_reg = port->mapbase + UART_TX;
604 	chan = dma_request_channel(mask, filter, param);
605 	if (!chan) {
606 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Tx)\n",
607 			__func__);
608 		return;
609 	}
610 	priv->chan_tx = chan;
611 
612 	/* Set Rx DMA */
613 	param = &priv->param_rx;
614 	param->dma_dev = &dma_dev->dev;
615 	param->chan_id = priv->port.line * 2 + 1; /* Rx = Tx + 1 */
616 
617 	param->rx_reg = port->mapbase + UART_RX;
618 	chan = dma_request_channel(mask, filter, param);
619 	if (!chan) {
620 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Rx)\n",
621 			__func__);
622 		dma_release_channel(priv->chan_tx);
623 		return;
624 	}
625 
626 	/* Get Consistent memory for DMA */
627 	priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize,
628 				    &priv->rx_buf_dma, GFP_KERNEL);
629 	priv->chan_rx = chan;
630 }
631 
632 static void pch_dma_rx_complete(void *arg)
633 {
634 	struct eg20t_port *priv = arg;
635 	struct uart_port *port = &priv->port;
636 	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
637 	int count;
638 
639 	if (!tty) {
640 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
641 		return;
642 	}
643 
644 	dma_sync_sg_for_cpu(port->dev, &priv->sg_rx, 1, DMA_FROM_DEVICE);
645 	count = dma_push_rx(priv, priv->trigger_level);
646 	if (count)
647 		tty_flip_buffer_push(tty);
648 	tty_kref_put(tty);
649 	async_tx_ack(priv->desc_rx);
650 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
651 }
652 
653 static void pch_dma_tx_complete(void *arg)
654 {
655 	struct eg20t_port *priv = arg;
656 	struct uart_port *port = &priv->port;
657 	struct circ_buf *xmit = &port->state->xmit;
658 	struct scatterlist *sg = priv->sg_tx_p;
659 	int i;
660 
661 	for (i = 0; i < priv->nent; i++, sg++) {
662 		xmit->tail += sg_dma_len(sg);
663 		port->icount.tx += sg_dma_len(sg);
664 	}
665 	xmit->tail &= UART_XMIT_SIZE - 1;
666 	async_tx_ack(priv->desc_tx);
667 	dma_unmap_sg(port->dev, sg, priv->nent, DMA_TO_DEVICE);
668 	priv->tx_dma_use = 0;
669 	priv->nent = 0;
670 	kfree(priv->sg_tx_p);
671 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
672 }
673 
674 static int pop_tx(struct eg20t_port *priv, int size)
675 {
676 	int count = 0;
677 	struct uart_port *port = &priv->port;
678 	struct circ_buf *xmit = &port->state->xmit;
679 
680 	if (uart_tx_stopped(port) || uart_circ_empty(xmit) || count >= size)
681 		goto pop_tx_end;
682 
683 	do {
684 		int cnt_to_end =
685 		    CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
686 		int sz = min(size - count, cnt_to_end);
687 		pch_uart_hal_write(priv, &xmit->buf[xmit->tail], sz);
688 		xmit->tail = (xmit->tail + sz) & (UART_XMIT_SIZE - 1);
689 		count += sz;
690 	} while (!uart_circ_empty(xmit) && count < size);
691 
692 pop_tx_end:
693 	dev_dbg(priv->port.dev, "%d characters. Remained %d characters.(%lu)\n",
694 		 count, size - count, jiffies);
695 
696 	return count;
697 }
698 
699 static int handle_rx_to(struct eg20t_port *priv)
700 {
701 	struct pch_uart_buffer *buf;
702 	int rx_size;
703 	int ret;
704 	if (!priv->start_rx) {
705 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
706 		return 0;
707 	}
708 	buf = &priv->rxbuf;
709 	do {
710 		rx_size = pch_uart_hal_read(priv, buf->buf, buf->size);
711 		ret = push_rx(priv, buf->buf, rx_size);
712 		if (ret)
713 			return 0;
714 	} while (rx_size == buf->size);
715 
716 	return PCH_UART_HANDLED_RX_INT;
717 }
718 
719 static int handle_rx(struct eg20t_port *priv)
720 {
721 	return handle_rx_to(priv);
722 }
723 
724 static int dma_handle_rx(struct eg20t_port *priv)
725 {
726 	struct uart_port *port = &priv->port;
727 	struct dma_async_tx_descriptor *desc;
728 	struct scatterlist *sg;
729 
730 	priv = container_of(port, struct eg20t_port, port);
731 	sg = &priv->sg_rx;
732 
733 	sg_init_table(&priv->sg_rx, 1); /* Initialize SG table */
734 
735 	sg_dma_len(sg) = priv->trigger_level;
736 
737 	sg_set_page(&priv->sg_rx, virt_to_page(priv->rx_buf_virt),
738 		     sg_dma_len(sg), (unsigned long)priv->rx_buf_virt &
739 		     ~PAGE_MASK);
740 
741 	sg_dma_address(sg) = priv->rx_buf_dma;
742 
743 	desc = priv->chan_rx->device->device_prep_slave_sg(priv->chan_rx,
744 			sg, 1, DMA_FROM_DEVICE,
745 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
746 
747 	if (!desc)
748 		return 0;
749 
750 	priv->desc_rx = desc;
751 	desc->callback = pch_dma_rx_complete;
752 	desc->callback_param = priv;
753 	desc->tx_submit(desc);
754 	dma_async_issue_pending(priv->chan_rx);
755 
756 	return PCH_UART_HANDLED_RX_INT;
757 }
758 
759 static unsigned int handle_tx(struct eg20t_port *priv)
760 {
761 	struct uart_port *port = &priv->port;
762 	struct circ_buf *xmit = &port->state->xmit;
763 	int fifo_size;
764 	int tx_size;
765 	int size;
766 	int tx_empty;
767 
768 	if (!priv->start_tx) {
769 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
770 			__func__, jiffies);
771 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
772 		priv->tx_empty = 1;
773 		return 0;
774 	}
775 
776 	fifo_size = max(priv->fifo_size, 1);
777 	tx_empty = 1;
778 	if (pop_tx_x(priv, xmit->buf)) {
779 		pch_uart_hal_write(priv, xmit->buf, 1);
780 		port->icount.tx++;
781 		tx_empty = 0;
782 		fifo_size--;
783 	}
784 	size = min(xmit->head - xmit->tail, fifo_size);
785 	if (size < 0)
786 		size = fifo_size;
787 
788 	tx_size = pop_tx(priv, size);
789 	if (tx_size > 0) {
790 		port->icount.tx += tx_size;
791 		tx_empty = 0;
792 	}
793 
794 	priv->tx_empty = tx_empty;
795 
796 	if (tx_empty) {
797 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
798 		uart_write_wakeup(port);
799 	}
800 
801 	return PCH_UART_HANDLED_TX_INT;
802 }
803 
804 static unsigned int dma_handle_tx(struct eg20t_port *priv)
805 {
806 	struct uart_port *port = &priv->port;
807 	struct circ_buf *xmit = &port->state->xmit;
808 	struct scatterlist *sg;
809 	int nent;
810 	int fifo_size;
811 	int tx_empty;
812 	struct dma_async_tx_descriptor *desc;
813 	int num;
814 	int i;
815 	int bytes;
816 	int size;
817 	int rem;
818 
819 	if (!priv->start_tx) {
820 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
821 			__func__, jiffies);
822 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
823 		priv->tx_empty = 1;
824 		return 0;
825 	}
826 
827 	if (priv->tx_dma_use) {
828 		dev_dbg(priv->port.dev, "%s:Tx is not completed. (%lu)\n",
829 			__func__, jiffies);
830 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
831 		priv->tx_empty = 1;
832 		return 0;
833 	}
834 
835 	fifo_size = max(priv->fifo_size, 1);
836 	tx_empty = 1;
837 	if (pop_tx_x(priv, xmit->buf)) {
838 		pch_uart_hal_write(priv, xmit->buf, 1);
839 		port->icount.tx++;
840 		tx_empty = 0;
841 		fifo_size--;
842 	}
843 
844 	bytes = min((int)CIRC_CNT(xmit->head, xmit->tail,
845 			     UART_XMIT_SIZE), CIRC_CNT_TO_END(xmit->head,
846 			     xmit->tail, UART_XMIT_SIZE));
847 	if (!bytes) {
848 		dev_dbg(priv->port.dev, "%s 0 bytes return\n", __func__);
849 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
850 		uart_write_wakeup(port);
851 		return 0;
852 	}
853 
854 	if (bytes > fifo_size) {
855 		num = bytes / fifo_size + 1;
856 		size = fifo_size;
857 		rem = bytes % fifo_size;
858 	} else {
859 		num = 1;
860 		size = bytes;
861 		rem = bytes;
862 	}
863 
864 	dev_dbg(priv->port.dev, "%s num=%d size=%d rem=%d\n",
865 		__func__, num, size, rem);
866 
867 	priv->tx_dma_use = 1;
868 
869 	priv->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
870 
871 	sg_init_table(priv->sg_tx_p, num); /* Initialize SG table */
872 	sg = priv->sg_tx_p;
873 
874 	for (i = 0; i < num; i++, sg++) {
875 		if (i == (num - 1))
876 			sg_set_page(sg, virt_to_page(xmit->buf),
877 				    rem, fifo_size * i);
878 		else
879 			sg_set_page(sg, virt_to_page(xmit->buf),
880 				    size, fifo_size * i);
881 	}
882 
883 	sg = priv->sg_tx_p;
884 	nent = dma_map_sg(port->dev, sg, num, DMA_TO_DEVICE);
885 	if (!nent) {
886 		dev_err(priv->port.dev, "%s:dma_map_sg Failed\n", __func__);
887 		return 0;
888 	}
889 	priv->nent = nent;
890 
891 	for (i = 0; i < nent; i++, sg++) {
892 		sg->offset = (xmit->tail & (UART_XMIT_SIZE - 1)) +
893 			      fifo_size * i;
894 		sg_dma_address(sg) = (sg_dma_address(sg) &
895 				    ~(UART_XMIT_SIZE - 1)) + sg->offset;
896 		if (i == (nent - 1))
897 			sg_dma_len(sg) = rem;
898 		else
899 			sg_dma_len(sg) = size;
900 	}
901 
902 	desc = priv->chan_tx->device->device_prep_slave_sg(priv->chan_tx,
903 					priv->sg_tx_p, nent, DMA_TO_DEVICE,
904 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
905 	if (!desc) {
906 		dev_err(priv->port.dev, "%s:device_prep_slave_sg Failed\n",
907 			__func__);
908 		return 0;
909 	}
910 	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, nent, DMA_TO_DEVICE);
911 	priv->desc_tx = desc;
912 	desc->callback = pch_dma_tx_complete;
913 	desc->callback_param = priv;
914 
915 	desc->tx_submit(desc);
916 
917 	dma_async_issue_pending(priv->chan_tx);
918 
919 	return PCH_UART_HANDLED_TX_INT;
920 }
921 
922 static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
923 {
924 	u8 fcr = ioread8(priv->membase + UART_FCR);
925 
926 	/* Reset FIFO */
927 	fcr |= UART_FCR_CLEAR_RCVR;
928 	iowrite8(fcr, priv->membase + UART_FCR);
929 
930 	if (lsr & PCH_UART_LSR_ERR)
931 		dev_err(&priv->pdev->dev, "Error data in FIFO\n");
932 
933 	if (lsr & UART_LSR_FE)
934 		dev_err(&priv->pdev->dev, "Framing Error\n");
935 
936 	if (lsr & UART_LSR_PE)
937 		dev_err(&priv->pdev->dev, "Parity Error\n");
938 
939 	if (lsr & UART_LSR_OE)
940 		dev_err(&priv->pdev->dev, "Overrun Error\n");
941 }
942 
943 static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
944 {
945 	struct eg20t_port *priv = dev_id;
946 	unsigned int handled;
947 	u8 lsr;
948 	int ret = 0;
949 	unsigned int iid;
950 	unsigned long flags;
951 
952 	spin_lock_irqsave(&priv->port.lock, flags);
953 	handled = 0;
954 	while ((iid = pch_uart_hal_get_iid(priv)) > 1) {
955 		switch (iid) {
956 		case PCH_UART_IID_RLS:	/* Receiver Line Status */
957 			lsr = pch_uart_hal_get_line_status(priv);
958 			if (lsr & (PCH_UART_LSR_ERR | UART_LSR_FE |
959 						UART_LSR_PE | UART_LSR_OE)) {
960 				pch_uart_err_ir(priv, lsr);
961 				ret = PCH_UART_HANDLED_RX_ERR_INT;
962 			}
963 			break;
964 		case PCH_UART_IID_RDR:	/* Received Data Ready */
965 			if (priv->use_dma) {
966 				pch_uart_hal_disable_interrupt(priv,
967 							PCH_UART_HAL_RX_INT);
968 				ret = dma_handle_rx(priv);
969 				if (!ret)
970 					pch_uart_hal_enable_interrupt(priv,
971 							PCH_UART_HAL_RX_INT);
972 			} else {
973 				ret = handle_rx(priv);
974 			}
975 			break;
976 		case PCH_UART_IID_RDR_TO:	/* Received Data Ready
977 						   (FIFO Timeout) */
978 			ret = handle_rx_to(priv);
979 			break;
980 		case PCH_UART_IID_THRE:	/* Transmitter Holding Register
981 						   Empty */
982 			if (priv->use_dma)
983 				ret = dma_handle_tx(priv);
984 			else
985 				ret = handle_tx(priv);
986 			break;
987 		case PCH_UART_IID_MS:	/* Modem Status */
988 			ret = PCH_UART_HANDLED_MS_INT;
989 			break;
990 		default:	/* Never junp to this label */
991 			dev_err(priv->port.dev, "%s:iid=%d (%lu)\n", __func__,
992 				iid, jiffies);
993 			ret = -1;
994 			break;
995 		}
996 		handled |= (unsigned int)ret;
997 	}
998 	if (handled == 0 && iid <= 1) {
999 		if (priv->int_dis_flag)
1000 			priv->int_dis_flag = 0;
1001 	}
1002 
1003 	spin_unlock_irqrestore(&priv->port.lock, flags);
1004 	return IRQ_RETVAL(handled);
1005 }
1006 
1007 /* This function tests whether the transmitter fifo and shifter for the port
1008 						described by 'port' is empty. */
1009 static unsigned int pch_uart_tx_empty(struct uart_port *port)
1010 {
1011 	struct eg20t_port *priv;
1012 	int ret;
1013 	priv = container_of(port, struct eg20t_port, port);
1014 	if (priv->tx_empty)
1015 		ret = TIOCSER_TEMT;
1016 	else
1017 		ret = 0;
1018 
1019 	return ret;
1020 }
1021 
1022 /* Returns the current state of modem control inputs. */
1023 static unsigned int pch_uart_get_mctrl(struct uart_port *port)
1024 {
1025 	struct eg20t_port *priv;
1026 	u8 modem;
1027 	unsigned int ret = 0;
1028 
1029 	priv = container_of(port, struct eg20t_port, port);
1030 	modem = pch_uart_hal_get_modem(priv);
1031 
1032 	if (modem & UART_MSR_DCD)
1033 		ret |= TIOCM_CAR;
1034 
1035 	if (modem & UART_MSR_RI)
1036 		ret |= TIOCM_RNG;
1037 
1038 	if (modem & UART_MSR_DSR)
1039 		ret |= TIOCM_DSR;
1040 
1041 	if (modem & UART_MSR_CTS)
1042 		ret |= TIOCM_CTS;
1043 
1044 	return ret;
1045 }
1046 
1047 static void pch_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1048 {
1049 	u32 mcr = 0;
1050 	struct eg20t_port *priv = container_of(port, struct eg20t_port, port);
1051 
1052 	if (mctrl & TIOCM_DTR)
1053 		mcr |= UART_MCR_DTR;
1054 	if (mctrl & TIOCM_RTS)
1055 		mcr |= UART_MCR_RTS;
1056 	if (mctrl & TIOCM_LOOP)
1057 		mcr |= UART_MCR_LOOP;
1058 
1059 	if (priv->mcr & UART_MCR_AFE)
1060 		mcr |= UART_MCR_AFE;
1061 
1062 	if (mctrl)
1063 		iowrite8(mcr, priv->membase + UART_MCR);
1064 }
1065 
1066 static void pch_uart_stop_tx(struct uart_port *port)
1067 {
1068 	struct eg20t_port *priv;
1069 	priv = container_of(port, struct eg20t_port, port);
1070 	priv->start_tx = 0;
1071 	priv->tx_dma_use = 0;
1072 }
1073 
1074 static void pch_uart_start_tx(struct uart_port *port)
1075 {
1076 	struct eg20t_port *priv;
1077 
1078 	priv = container_of(port, struct eg20t_port, port);
1079 
1080 	if (priv->use_dma) {
1081 		if (priv->tx_dma_use) {
1082 			dev_dbg(priv->port.dev, "%s : Tx DMA is NOT empty.\n",
1083 				__func__);
1084 			return;
1085 		}
1086 	}
1087 
1088 	priv->start_tx = 1;
1089 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
1090 }
1091 
1092 static void pch_uart_stop_rx(struct uart_port *port)
1093 {
1094 	struct eg20t_port *priv;
1095 	priv = container_of(port, struct eg20t_port, port);
1096 	priv->start_rx = 0;
1097 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
1098 	priv->int_dis_flag = 1;
1099 }
1100 
1101 /* Enable the modem status interrupts. */
1102 static void pch_uart_enable_ms(struct uart_port *port)
1103 {
1104 	struct eg20t_port *priv;
1105 	priv = container_of(port, struct eg20t_port, port);
1106 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_MS_INT);
1107 }
1108 
1109 /* Control the transmission of a break signal. */
1110 static void pch_uart_break_ctl(struct uart_port *port, int ctl)
1111 {
1112 	struct eg20t_port *priv;
1113 	unsigned long flags;
1114 
1115 	priv = container_of(port, struct eg20t_port, port);
1116 	spin_lock_irqsave(&port->lock, flags);
1117 	pch_uart_hal_set_break(priv, ctl);
1118 	spin_unlock_irqrestore(&port->lock, flags);
1119 }
1120 
1121 /* Grab any interrupt resources and initialise any low level driver state. */
1122 static int pch_uart_startup(struct uart_port *port)
1123 {
1124 	struct eg20t_port *priv;
1125 	int ret;
1126 	int fifo_size;
1127 	int trigger_level;
1128 
1129 	priv = container_of(port, struct eg20t_port, port);
1130 	priv->tx_empty = 1;
1131 
1132 	if (port->uartclk)
1133 		priv->base_baud = port->uartclk;
1134 	else
1135 		port->uartclk = priv->base_baud;
1136 
1137 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1138 	ret = pch_uart_hal_set_line(priv, default_baud,
1139 			      PCH_UART_HAL_PARITY_NONE, PCH_UART_HAL_8BIT,
1140 			      PCH_UART_HAL_STB1);
1141 	if (ret)
1142 		return ret;
1143 
1144 	switch (priv->fifo_size) {
1145 	case 256:
1146 		fifo_size = PCH_UART_HAL_FIFO256;
1147 		break;
1148 	case 64:
1149 		fifo_size = PCH_UART_HAL_FIFO64;
1150 		break;
1151 	case 16:
1152 		fifo_size = PCH_UART_HAL_FIFO16;
1153 	case 1:
1154 	default:
1155 		fifo_size = PCH_UART_HAL_FIFO_DIS;
1156 		break;
1157 	}
1158 
1159 	switch (priv->trigger) {
1160 	case PCH_UART_HAL_TRIGGER1:
1161 		trigger_level = 1;
1162 		break;
1163 	case PCH_UART_HAL_TRIGGER_L:
1164 		trigger_level = priv->fifo_size / 4;
1165 		break;
1166 	case PCH_UART_HAL_TRIGGER_M:
1167 		trigger_level = priv->fifo_size / 2;
1168 		break;
1169 	case PCH_UART_HAL_TRIGGER_H:
1170 	default:
1171 		trigger_level = priv->fifo_size - (priv->fifo_size / 8);
1172 		break;
1173 	}
1174 
1175 	priv->trigger_level = trigger_level;
1176 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1177 				    fifo_size, priv->trigger);
1178 	if (ret < 0)
1179 		return ret;
1180 
1181 	ret = request_irq(priv->port.irq, pch_uart_interrupt, IRQF_SHARED,
1182 			KBUILD_MODNAME, priv);
1183 	if (ret < 0)
1184 		return ret;
1185 
1186 	if (priv->use_dma)
1187 		pch_request_dma(port);
1188 
1189 	priv->start_rx = 1;
1190 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
1191 	uart_update_timeout(port, CS8, default_baud);
1192 
1193 	return 0;
1194 }
1195 
1196 static void pch_uart_shutdown(struct uart_port *port)
1197 {
1198 	struct eg20t_port *priv;
1199 	int ret;
1200 
1201 	priv = container_of(port, struct eg20t_port, port);
1202 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1203 	pch_uart_hal_fifo_reset(priv, PCH_UART_HAL_CLR_ALL_FIFO);
1204 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1205 			      PCH_UART_HAL_FIFO_DIS, PCH_UART_HAL_TRIGGER1);
1206 	if (ret)
1207 		dev_err(priv->port.dev,
1208 			"pch_uart_hal_set_fifo Failed(ret=%d)\n", ret);
1209 
1210 	if (priv->use_dma_flag)
1211 		pch_free_dma(port);
1212 
1213 	free_irq(priv->port.irq, priv);
1214 }
1215 
1216 /* Change the port parameters, including word length, parity, stop
1217  *bits.  Update read_status_mask and ignore_status_mask to indicate
1218  *the types of events we are interested in receiving.  */
1219 static void pch_uart_set_termios(struct uart_port *port,
1220 				 struct ktermios *termios, struct ktermios *old)
1221 {
1222 	int baud;
1223 	int rtn;
1224 	unsigned int parity, bits, stb;
1225 	struct eg20t_port *priv;
1226 	unsigned long flags;
1227 
1228 	priv = container_of(port, struct eg20t_port, port);
1229 	switch (termios->c_cflag & CSIZE) {
1230 	case CS5:
1231 		bits = PCH_UART_HAL_5BIT;
1232 		break;
1233 	case CS6:
1234 		bits = PCH_UART_HAL_6BIT;
1235 		break;
1236 	case CS7:
1237 		bits = PCH_UART_HAL_7BIT;
1238 		break;
1239 	default:		/* CS8 */
1240 		bits = PCH_UART_HAL_8BIT;
1241 		break;
1242 	}
1243 	if (termios->c_cflag & CSTOPB)
1244 		stb = PCH_UART_HAL_STB2;
1245 	else
1246 		stb = PCH_UART_HAL_STB1;
1247 
1248 	if (termios->c_cflag & PARENB) {
1249 		if (!(termios->c_cflag & PARODD))
1250 			parity = PCH_UART_HAL_PARITY_ODD;
1251 		else
1252 			parity = PCH_UART_HAL_PARITY_EVEN;
1253 
1254 	} else {
1255 		parity = PCH_UART_HAL_PARITY_NONE;
1256 	}
1257 
1258 	/* Only UART0 has auto hardware flow function */
1259 	if ((termios->c_cflag & CRTSCTS) && (priv->fifo_size == 256))
1260 		priv->mcr |= UART_MCR_AFE;
1261 	else
1262 		priv->mcr &= ~UART_MCR_AFE;
1263 
1264 	termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
1265 
1266 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
1267 
1268 	spin_lock_irqsave(&port->lock, flags);
1269 
1270 	uart_update_timeout(port, termios->c_cflag, baud);
1271 	rtn = pch_uart_hal_set_line(priv, baud, parity, bits, stb);
1272 	if (rtn)
1273 		goto out;
1274 
1275 	/* Don't rewrite B0 */
1276 	if (tty_termios_baud_rate(termios))
1277 		tty_termios_encode_baud_rate(termios, baud, baud);
1278 
1279 out:
1280 	spin_unlock_irqrestore(&port->lock, flags);
1281 }
1282 
1283 static const char *pch_uart_type(struct uart_port *port)
1284 {
1285 	return KBUILD_MODNAME;
1286 }
1287 
1288 static void pch_uart_release_port(struct uart_port *port)
1289 {
1290 	struct eg20t_port *priv;
1291 
1292 	priv = container_of(port, struct eg20t_port, port);
1293 	pci_iounmap(priv->pdev, priv->membase);
1294 	pci_release_regions(priv->pdev);
1295 }
1296 
1297 static int pch_uart_request_port(struct uart_port *port)
1298 {
1299 	struct eg20t_port *priv;
1300 	int ret;
1301 	void __iomem *membase;
1302 
1303 	priv = container_of(port, struct eg20t_port, port);
1304 	ret = pci_request_regions(priv->pdev, KBUILD_MODNAME);
1305 	if (ret < 0)
1306 		return -EBUSY;
1307 
1308 	membase = pci_iomap(priv->pdev, 1, 0);
1309 	if (!membase) {
1310 		pci_release_regions(priv->pdev);
1311 		return -EBUSY;
1312 	}
1313 	priv->membase = port->membase = membase;
1314 
1315 	return 0;
1316 }
1317 
1318 static void pch_uart_config_port(struct uart_port *port, int type)
1319 {
1320 	struct eg20t_port *priv;
1321 
1322 	priv = container_of(port, struct eg20t_port, port);
1323 	if (type & UART_CONFIG_TYPE) {
1324 		port->type = priv->port_type;
1325 		pch_uart_request_port(port);
1326 	}
1327 }
1328 
1329 static int pch_uart_verify_port(struct uart_port *port,
1330 				struct serial_struct *serinfo)
1331 {
1332 	struct eg20t_port *priv;
1333 
1334 	priv = container_of(port, struct eg20t_port, port);
1335 	if (serinfo->flags & UPF_LOW_LATENCY) {
1336 		dev_info(priv->port.dev,
1337 			"PCH UART : Use PIO Mode (without DMA)\n");
1338 		priv->use_dma = 0;
1339 		serinfo->flags &= ~UPF_LOW_LATENCY;
1340 	} else {
1341 #ifndef CONFIG_PCH_DMA
1342 		dev_err(priv->port.dev, "%s : PCH DMA is not Loaded.\n",
1343 			__func__);
1344 		return -EOPNOTSUPP;
1345 #endif
1346 		priv->use_dma = 1;
1347 		priv->use_dma_flag = 1;
1348 		dev_info(priv->port.dev, "PCH UART : Use DMA Mode\n");
1349 	}
1350 
1351 	return 0;
1352 }
1353 
1354 static struct uart_ops pch_uart_ops = {
1355 	.tx_empty = pch_uart_tx_empty,
1356 	.set_mctrl = pch_uart_set_mctrl,
1357 	.get_mctrl = pch_uart_get_mctrl,
1358 	.stop_tx = pch_uart_stop_tx,
1359 	.start_tx = pch_uart_start_tx,
1360 	.stop_rx = pch_uart_stop_rx,
1361 	.enable_ms = pch_uart_enable_ms,
1362 	.break_ctl = pch_uart_break_ctl,
1363 	.startup = pch_uart_startup,
1364 	.shutdown = pch_uart_shutdown,
1365 	.set_termios = pch_uart_set_termios,
1366 /*	.pm		= pch_uart_pm,		Not supported yet */
1367 /*	.set_wake	= pch_uart_set_wake,	Not supported yet */
1368 	.type = pch_uart_type,
1369 	.release_port = pch_uart_release_port,
1370 	.request_port = pch_uart_request_port,
1371 	.config_port = pch_uart_config_port,
1372 	.verify_port = pch_uart_verify_port
1373 };
1374 
1375 static struct uart_driver pch_uart_driver = {
1376 	.owner = THIS_MODULE,
1377 	.driver_name = KBUILD_MODNAME,
1378 	.dev_name = PCH_UART_DRIVER_DEVICE,
1379 	.major = 0,
1380 	.minor = 0,
1381 	.nr = PCH_UART_NR,
1382 };
1383 
1384 static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
1385 					     const struct pci_device_id *id)
1386 {
1387 	struct eg20t_port *priv;
1388 	int ret;
1389 	unsigned int iobase;
1390 	unsigned int mapbase;
1391 	unsigned char *rxbuf;
1392 	int fifosize, base_baud;
1393 	int port_type;
1394 	struct pch_uart_driver_data *board;
1395 
1396 	board = &drv_dat[id->driver_data];
1397 	port_type = board->port_type;
1398 
1399 	priv = kzalloc(sizeof(struct eg20t_port), GFP_KERNEL);
1400 	if (priv == NULL)
1401 		goto init_port_alloc_err;
1402 
1403 	rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
1404 	if (!rxbuf)
1405 		goto init_port_free_txbuf;
1406 
1407 	base_baud = 1843200; /* 1.8432MHz */
1408 
1409 	/* quirk for CM-iTC board */
1410 	if (strstr(dmi_get_system_info(DMI_BOARD_NAME), "CM-iTC"))
1411 		base_baud = 192000000; /* 192.0MHz */
1412 
1413 	switch (port_type) {
1414 	case PORT_UNKNOWN:
1415 		fifosize = 256; /* EG20T/ML7213: UART0 */
1416 		break;
1417 	case PORT_8250:
1418 		fifosize = 64; /* EG20T:UART1~3  ML7213: UART1~2*/
1419 		break;
1420 	default:
1421 		dev_err(&pdev->dev, "Invalid Port Type(=%d)\n", port_type);
1422 		goto init_port_hal_free;
1423 	}
1424 
1425 	iobase = pci_resource_start(pdev, 0);
1426 	mapbase = pci_resource_start(pdev, 1);
1427 	priv->mapbase = mapbase;
1428 	priv->iobase = iobase;
1429 	priv->pdev = pdev;
1430 	priv->tx_empty = 1;
1431 	priv->rxbuf.buf = rxbuf;
1432 	priv->rxbuf.size = PAGE_SIZE;
1433 
1434 	priv->fifo_size = fifosize;
1435 	priv->base_baud = base_baud;
1436 	priv->port_type = PORT_MAX_8250 + port_type + 1;
1437 	priv->port.dev = &pdev->dev;
1438 	priv->port.iobase = iobase;
1439 	priv->port.membase = NULL;
1440 	priv->port.mapbase = mapbase;
1441 	priv->port.irq = pdev->irq;
1442 	priv->port.iotype = UPIO_PORT;
1443 	priv->port.ops = &pch_uart_ops;
1444 	priv->port.flags = UPF_BOOT_AUTOCONF;
1445 	priv->port.fifosize = fifosize;
1446 	priv->port.line = board->line_no;
1447 	priv->trigger = PCH_UART_HAL_TRIGGER_M;
1448 
1449 	spin_lock_init(&priv->port.lock);
1450 
1451 	pci_set_drvdata(pdev, priv);
1452 	pch_uart_hal_request(pdev, fifosize, base_baud);
1453 
1454 	ret = uart_add_one_port(&pch_uart_driver, &priv->port);
1455 	if (ret < 0)
1456 		goto init_port_hal_free;
1457 
1458 	return priv;
1459 
1460 init_port_hal_free:
1461 	free_page((unsigned long)rxbuf);
1462 init_port_free_txbuf:
1463 	kfree(priv);
1464 init_port_alloc_err:
1465 
1466 	return NULL;
1467 }
1468 
1469 static void pch_uart_exit_port(struct eg20t_port *priv)
1470 {
1471 	uart_remove_one_port(&pch_uart_driver, &priv->port);
1472 	pci_set_drvdata(priv->pdev, NULL);
1473 	free_page((unsigned long)priv->rxbuf.buf);
1474 }
1475 
1476 static void pch_uart_pci_remove(struct pci_dev *pdev)
1477 {
1478 	struct eg20t_port *priv;
1479 
1480 	priv = (struct eg20t_port *)pci_get_drvdata(pdev);
1481 	pch_uart_exit_port(priv);
1482 	pci_disable_device(pdev);
1483 	kfree(priv);
1484 	return;
1485 }
1486 #ifdef CONFIG_PM
1487 static int pch_uart_pci_suspend(struct pci_dev *pdev, pm_message_t state)
1488 {
1489 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1490 
1491 	uart_suspend_port(&pch_uart_driver, &priv->port);
1492 
1493 	pci_save_state(pdev);
1494 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1495 	return 0;
1496 }
1497 
1498 static int pch_uart_pci_resume(struct pci_dev *pdev)
1499 {
1500 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1501 	int ret;
1502 
1503 	pci_set_power_state(pdev, PCI_D0);
1504 	pci_restore_state(pdev);
1505 
1506 	ret = pci_enable_device(pdev);
1507 	if (ret) {
1508 		dev_err(&pdev->dev,
1509 		"%s-pci_enable_device failed(ret=%d) ", __func__, ret);
1510 		return ret;
1511 	}
1512 
1513 	uart_resume_port(&pch_uart_driver, &priv->port);
1514 
1515 	return 0;
1516 }
1517 #else
1518 #define pch_uart_pci_suspend NULL
1519 #define pch_uart_pci_resume NULL
1520 #endif
1521 
1522 static DEFINE_PCI_DEVICE_TABLE(pch_uart_pci_id) = {
1523 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8811),
1524 	 .driver_data = pch_et20t_uart0},
1525 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8812),
1526 	 .driver_data = pch_et20t_uart1},
1527 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8813),
1528 	 .driver_data = pch_et20t_uart2},
1529 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8814),
1530 	 .driver_data = pch_et20t_uart3},
1531 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8027),
1532 	 .driver_data = pch_ml7213_uart0},
1533 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8028),
1534 	 .driver_data = pch_ml7213_uart1},
1535 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8029),
1536 	 .driver_data = pch_ml7213_uart2},
1537 	{0,},
1538 };
1539 
1540 static int __devinit pch_uart_pci_probe(struct pci_dev *pdev,
1541 					const struct pci_device_id *id)
1542 {
1543 	int ret;
1544 	struct eg20t_port *priv;
1545 
1546 	ret = pci_enable_device(pdev);
1547 	if (ret < 0)
1548 		goto probe_error;
1549 
1550 	priv = pch_uart_init_port(pdev, id);
1551 	if (!priv) {
1552 		ret = -EBUSY;
1553 		goto probe_disable_device;
1554 	}
1555 	pci_set_drvdata(pdev, priv);
1556 
1557 	return ret;
1558 
1559 probe_disable_device:
1560 	pci_disable_device(pdev);
1561 probe_error:
1562 	return ret;
1563 }
1564 
1565 static struct pci_driver pch_uart_pci_driver = {
1566 	.name = "pch_uart",
1567 	.id_table = pch_uart_pci_id,
1568 	.probe = pch_uart_pci_probe,
1569 	.remove = __devexit_p(pch_uart_pci_remove),
1570 	.suspend = pch_uart_pci_suspend,
1571 	.resume = pch_uart_pci_resume,
1572 };
1573 
1574 static int __init pch_uart_module_init(void)
1575 {
1576 	int ret;
1577 
1578 	/* register as UART driver */
1579 	ret = uart_register_driver(&pch_uart_driver);
1580 	if (ret < 0)
1581 		return ret;
1582 
1583 	/* register as PCI driver */
1584 	ret = pci_register_driver(&pch_uart_pci_driver);
1585 	if (ret < 0)
1586 		uart_unregister_driver(&pch_uart_driver);
1587 
1588 	return ret;
1589 }
1590 module_init(pch_uart_module_init);
1591 
1592 static void __exit pch_uart_module_exit(void)
1593 {
1594 	pci_unregister_driver(&pch_uart_pci_driver);
1595 	uart_unregister_driver(&pch_uart_driver);
1596 }
1597 module_exit(pch_uart_module_exit);
1598 
1599 MODULE_LICENSE("GPL v2");
1600 MODULE_DESCRIPTION("Intel EG20T PCH UART PCI Driver");
1601 module_param(default_baud, uint, S_IRUGO);
1602